Download Alan`s DAT Biology Notes edited by scsc7211

scsc7211’s Version of Alan’s DAT Biology Notes
Chapter 1: Basis of Life (1& 2 in Cliff's)
Chapter 2: Reproduction (5-cell division &12-human reproduction in Cliff's)
Chapter 3: Genetics (6&7 in Cliff's)
Chapter 4: Embryology (12 in Cliff's)
Chapter 5: Vascular System in Plants and Animals (10&11 in Cliff's)
Chapter 6: Endocrinology (11 in Cliff's)
Chapter 7: Neuroscience (11 in Cliff's)
Chapter 8: Respiration (3 in Cliff's)
Chapter 9: Autotrophic Nutrition (4 in Cliff's)
Chapter 10: Muscles and Locomotion (11 in Cliff's)
Chapter 11: Digestion (11 in Cliff's)
Chapter 12: Excretion (11 in Cliff's)
Chapter 12.5: Integumentary
Chapter 13: Animal Behavior (13 in Cliff's)
Chapter 14: Ecology (14 in Cliff's)
Chapter 15: Classification (9 in Cliff's)
Chapter 16: Evolution (8 in Cliff's)
Chapter 1 – Basis of Life
Ingestion – acquisition of food
Assimilation – building of new tissues from digested food
Monosaccharide – (carb) single sugar subunit
Disaccharide – glycosidic linkage
Ex:glucose+fructose = sucrose, glucose+galactose=lactose, glucose+glucose=maltose
Polysaccharide – (carb) polymer, insoluble in water;
ex: glycogen (energy storage in animals), starch (energy storage in plants), Cellulose (polymer of betaglucose/structural), Chitin (like cellulose, but glucose has a nitrogen/structural molecular in fungi and exoskeleton of
insects, arthropods, and mollusks)
Lipids – (2:1 H/O ratio) 3 FA bonded to glycerol=triglyceride; chief means of food storage

Major component of adipose tissue

Steroids (estradiol, testosterone, cholesterol), waxes, carotenoids, porphyrins
Proteins - polymers of AA joined by peptide bond / 1* = AA sequence, 2* = folding (alpha beta)

Hormones (ACTH & insulin), Enzymes, structural pro (collagen), transport (hemoglobin),
antibodies
Enzymes – lower activation E & inc. rate of rxn / do not affect overall E

Higher temp = inc enzyme action / optimal pH = 7.2 (except pepsin & pancreas)

Competitive inhibitors compete w/ substrate for binding at ACTIVE site; can be overcome by
adding more substrate; Vmax not affected

Noncompetitive inhibitors bind at allosteric site; diminishes Vmax

Holoenzyme: union of cofactor and apoenzyme

Cooperativity: enzyme more receptive to additional substrate after one substrate molecule attaches
to an active site
o Ex: Hemoglobin- binding capacity to additional oxygen increases after first oxygen binds
to active site
Prokaryotes – bacteria, cell wall, NO nucleus (instead nucleoid region”naked DNA”), NO memb-bound organelles,
ribosomes smaller and no mem (70S, w/ 50S and 30S VS 80S w/60S 40S in Euk.), mesosomes (invaginations of
membrane), flagella of prokaryotes not constructed of microtubules
Eukaryotes – cell wall in fungi & plants, nucleus, membrane-bound organelles
Nucleus contains nucleolus(sometimes more than one): concentrations of DNA in the process of
manufacturing components of ribosomes
Nucleolus: concentrations of DNA in the process of manufacturing components of ribosomes
Chromatin: the normal (non-replicating) form of DNA, spread out in a threadlike matrix
Endomembrane system: different membranes suspended in the cytoplasm
Includes (nuclear envelope, E.R., Golgi, lysosomes, vacuoles, vesicles, peroxisomes, and cell membrane
Does NOT include (mitochondria and chloroplasts)
Endoplasmic reticulum: extension of nuclear envelope – all of the proteins that will exit the cell are originally
delivered to the ER, then to the Golgi for export
Rough ER (ribosomes present)- creates glycoproteins by attaching polysaccharides to polypeptides
Smooth ER (ribosomes absent)- synthesis of lipids and hormones (often for export)/ in liver, involved in
breakdown of toxins, drugs, and toxic byproducts of cellular rxns
Golgi apparatus: modify (glycosylation) and package proteins and lipids into vesicles (spherical sacs that bud out
from the Golgi and often merge with the cellular membrane so contents are released to outside of cell)
Centrioles – microtubule involved in spindle organization during cell division/ NO membrane
Centromere – near middle of eukaryotic chromosomes where spindle fibers attach
Lysosome – membrane bound, involved in ingestion / hydrolytic enzymes. Low pH  so inactive in cytosol. NOT in
plant cells.
Peroxisomes- break down H2O2, fatty acids, amino acids. Common in liver and kidney cells. In plant cells, modify
by-products of photorespiration. In germinating seeds, glyoxysomes break down stored fatty acids
Mitochondria – exhibit maternal inheritance – carry out aerobic respiration
Chloroplasts- Carry out photosynthesis – incorporate energy from sunlight into carbohydrates
Microtubules < intermediate filaments < microfilaments: three comprise cytoskeleton

Microtubules- made of tubulin, support for cellular activities, found in spindle apparatus, and
flagella

Int. filaments- maintain shape of cell

Microfilaments- made of actin, involved in motility, found in muscle cells and phagocytes
Flagella and cilia: 9+2 array – nine pairs of microtubules surrounding pair of microtubules
Centrioles and Basal body: centrioles- give rise to microtubules for spindle. Basal body- at base of flagella and
cilium and appear to organize their development
 Both made up of 9 triplets of microtubules arranged in circle
Central vacuole- occupy most of interior of certain plants. Exert turgor (pressure) on cell walls to maintain rigidity.
Store nutrients and fxns otherwise carried out by lysosomes in animal cells
Cell wall: found in plants, fungi, protists, and bacteria. Plants=cellulose, fungi=chitin (hydroxyl group of cellulose
replaced by nitrogen)
Extracellular matrix: area between adjacent cells – most common protein in region is collagen
Anchoring Junction: protein attachments between animal cells
 Desmosomes = “spot welds”; attach cells together and give cells mechanical strength- keratin (ex. skin cells)
Tight junctions = completely seal the spaces b/w cells and prevent cell leakage between animal cells (ex. intestinal
cells)
Communicating junctions:
 Gap junctions = allow animal cells to exchange ions and small molecules without cytoplasmic mixing and
for molecular communication/ made up of connexins.
 Plasmodesmata: narrow channels between plant cells. Narrow tube of ER, called desmotubule, surrounded
by cytoplasm and plasma membrane, passes through channel
Endosymbiotic Theory – mitochondria and chloroplasts originated as independent unicellular organisms living in
symbiosis with larger cells
Fluid Mosaic – lipids and proteins are free to move back and forth fluidly; diffuse laterally

Integral Membrane are embedded in membrane by hydrophobic interactions
o Transmembrane: integral that spans the entire membrane

Peripheral are stuck to integral membrane proteins by H bonding
Cell surface Receptors – type of integral membrane protein; three types: ligand-gated (open ion channel), catalytic,
and G-protein
G-Protein – use secondary messengers such as cAMP which amplify signal
Glycocalyx- carbohydrate coat that covers outer face of cell wall of some bacteria and outer face of plasma membrane
of some animal cells (adhesive capabilities, barrier to infection, or marker for cell recognition)
Bulk flow: collective movement of substances in same direction in response to pressure (ex. Blood moving through a
blood vessel)
Passive transport: (1) Simple diffusion: high to low (2) Osmosis: diffusion of water across membrane (3): Dialysis:
diffusion of solutes (4) Plasmolysis: movement of water out of cell, resulting in collapse (5): Facilitated diffusion:
solutes or water through channel protein (6) Countercurrent exchg: diffusion of substances between two regions in
which substances are moving by bulk flow in opposite directions
Plant v animal cell:
-Plant cells have/animal cells lack: cell walls, chloroplasts, and central vacuoles
-Animal cells have/plant cells lack: lysosomes, centrioles, and cholesterol
Chapter 2 – Reproduction
Marine reproduction strategies:
Oviparous – internal fertilization; lay eggs “egg birth”
Viviparous – internal fertilization; “live birth”
Ovoviviparous – internal fertilization; egg develops inside mother “egg live birth”
CELL DIVISION – nuclear division followed by cytokinesis
Cell cycle:
S phase – replicate genome (create chromatids)
G1 & G2 phase – gap phases
Mitosis – 2N=>2N, occurs in all dividing cells; 10% of cell cycle
1. Interphase (90% of time) – replication of genetic material resulting in sister chromatids
2. Prophase – chromatids condense into xsomes; nuclear envelope breaks down; microtubule spindles
form and attach to kinetochore of centromere
3. Metaphase – chromosomes align across metaphase plate
4. Anaphase – sister chromatids separate; shortest phase
5. Telophase – new nuclear membranes form (cleavage furrow forms); spindles disappear, and
chromosomes disperse into chromatin
6. Cytokinesis- in animal cells, a cleavage furrow forms and membrane is pinched in two by
microfilaments
a. PLANTS: vesicles from Golgi body migrate to central plane and fuse to form a cell plate,
followed by cell wall development; also, plants lack centrioles, and spindle is synthesized
by MTOCs that are not visible
Meiosis – occurs in sex cells, homologous chromosomes pair at meta plate (tetrads), crossing over can occur, 2N=>N
-
First Meiotic Division produces 2 daughter cells w/ N chromosomes w/ sister chrom
1. Prophase I – chromatids of homologous chromosomes pair up and exchange genetic material
(crossing over)- called synapsis. When tetrads (groups of four chromatids line up and
-
nonsister chromatids form close associations called chiasmata (legs of chromosomes
overlap). Tetrad with chiasmata is a synaptonemal complex
2. Metaphase I – tetrads align at plate; each pair attaches to a separate spindle

***Karyotyping performed here***
3. Anaphase I – homologous pairs pulled to opposite poles (disjunction) / distribution to the two
daughter cells is random w/ respect to parental origin
4. Telophase I – nuclear membrane forms around each nucleus, producing two haploid daughter
cells
Second division is very similar to mitosis. No chromosomal replication. Note that only one becomes
functional gamete in females (3 polar bodies are eventually degraded, while mature ovum is produced)
Inversion – chromosomal segment turned 180o
Translocation – 2 nonhomologous chromosomes interchange genes (attachment of all or part of one chromosome to
another)
***Mitochondrial DNA is an exception to the universality of the genetic code***
Nondisjunction – failure of homologous chromosomes to separate during Meiosis I or sister chromatids to separate
during Meiosis II; result in trisomy or monosomy; ex Down syndrome
Turner syndrome – sterile female lacking X chromosome; monosomy
Klinefelter Syndrome = 44 autosomes + XXY
Asexual Reproduction methods – production of offspring w/o fertilization

Binary Fission – prokaryotes (one celled amoebae, paramecia, algae, and bacteria); DNA
replicates, wall grows inward along midwall to make two equally sized cells

Budding – replication of nucleus followed by unequal cytokinesis. Develops as outgrowth, forms
smaller cell that will eventually grow to adult size; ex hydra & yeast

Regeneration – regrowth of lost body part; ex starfish, hydra, tadpole, salamander

***Parthenogenesis – unfertilized egg to adult organism; ex male bees and ants***
Asexual reproduction in plants
1. Spore formation- ALTERNATION OF GENERATIONS; diploid generation is succeeded by haploid
generation
a. Diploid sporophyte(spore-producing plant)  Haploid spores  haploid gametophyte (sex cellproducing plant)
b. Angiosperms: dominant is sporophyte, Mosses(bryophyte): gametophyte dominant
Angiosperms - flowering plants; flower is reproductive structure

Stamen – male organ; composed of stalk-like filament & sac-like anther (produces haploid spores
that develop into pollen)

Pistil – female organ; composed of stigma (catches pollen), style, and ovary

Sepals – green leaves cover and protect flower bud during early development

Fertilization –
1 sperm nucleus + 1 egg nucleus => zygote => embryo
1 sperm nucleus + 2 polar nuclei => 3n endosperm

Seed formation – Epicotyl (precursor of leaves), Cotyledons (seed leaves), Hypocotyl (develops
into lower stem and root), Endosperm (feeds embryo), Seed Coat (develops from outer covering
of ovule)
2.
Vegetative propagation- undifferentiated tissues in plants, meristems, provide a source of cells that can
develop into an adult plant
a. Natural Vegetative propagation
i. Bulbs- split to form several bulbs (tulips and daffodils)
ii. Tubers- underground stems with buds (eyes of potatoes)
iii. Runners- stems running above and along ground that produce new roots and upright
stems (strawberry and lawn grasses)
iv. Rhizomes (stolons): woody, underground stems (ferns and iris)
b. Artificial Vegetative propagation
i. Cut piece of stem can develop new roots - auxins used to accelerate root growth
ii. Layering- stems will take room when bent to ground and covered with soil (raspberries
and blackberries)
iii. The stem of one plant called the scion can be attached to rooted stem of closely related
plant (the stock). Cambium of both stems must be in contact for water transport
HUMAN REPRODUCTION
Gonads – male = testes, female = ovaries
Leydig cells –interstitial cells in the testes, secrete testosterone in presence of LH
Spermatogenesis – sperm production in seminiferous tubules; head = nucleus & tail = flagellum

acrosome – lysosome containing enzymes used to penetrate the egg
prostatic fluid – secreted by prostate; helps neutralize the acidic vaginal secretions to enhance sperms’ ability to swim;
also neutralizes seminal fluid (too acidic from metabolic waste of sperm)
Oogenesis – oocytes produced in ovaries
Capacitation – penultimate step in maturation of the spermatozoa while in the female, allows for egg penetration
Male Reproductive – path of sperm SEVEnUP
1. seminiferous tubules- production of sperm
2. epididymis- maturation and storage of sperm
3. vas deferens(2)- transfer sperm from both epididymis to urethra
4. ejaculatory duct
5. urethra
6. penis
Female Reproductive – fallopian tube opens to uterus (narrow end called cervix), cervix connects with vaginal canal
The Menstrual Cycle - divided into follicular, ovulation, luteal, menstruation
Follicular – FSH promotes development of follicle which secretes estrogen
Ovulation- peak in estrogen  LH surge  ovulation (midway through cycle)  mature follicle
bursts releasing ovum
3. Luteal – LH induces follicle to develop into corpus luteum which secretes estrogen and
progesterone-responsible for maintenance of endometrium (LH and FSH inhibited)
4. Menstruation –
o If ovum is not fertilized, corpus luteum atrophies  corpus albicans, and drop in estrogen
and progesterone cause endometrium to slough off
o If fertilized, placenta produces (Human chorionic gonadotropin) hCG (estrogen + proges
levels remain high)
Estrogen – thicken endometrium
Progesterone – development and maintenance of endometrial wall
1.
2.
Chapter 3 – Genetics
-Genes on the same chromosome will stay together unless crossing over occurs
-For a Dihybrid Cross make a punnet square that is 4X4. I.E. if the genotypes are TTPP and TtPp the four on top would
be (TP TP TP TP) and on the side would be (TP Tp tP tp)
Mendel’s Law of Segregation- one member of each chromosome pair migrates to an opposite pole (a gamete will
receive one allele or the other)
Mendel’s Law of Independent Assortment: Alleles of different genes (and their chromosomes) assort independently
during gamete formation
Incomplete Dominance – progeny phenotypes that are blends of parental phenotypes. Classic example is color in
snapdragons (dominant red crossed with recessive white produce PINK)
Codominance – both alleles are completely expressed;
Ex. Multiple alleles: BLOOD- A and B dominant and i recessive ( o = ii, A = IAIA or IAi, B=IAIA or IAi,
AB = IAIB)
Epistasis – occurs when one gene masks or modifies the expression of an other gene
Pleiotropy – single gene effects several phenotypic characteristics

Ex: Gene in pea plants that expressed seed texture also influences phenotype of starch metabolism and water
uptake

Ex 2: Sickle cell anemia
Polygenic inheritance: The interaction of many genes to shape a single phenotype. Polygenic inheritance is the
opposite of pleiotropy. Ex: human height
Sex-Linked Inheritance (X-linked)–much more common in MALES- gene carried on X chromosome; ex hemophilia
& color blindness
X-Inactivation- During embryonic development in female mammals, one X chromosome remains coiled as compact
body, called Barr body. This happens randomly in embryonic cells, so fully developed fetus will have some groups
with one X active and some with the other. Ex: calico cats
Nondisjunction- failure of one or more chromosome pairs or chromatids to segregate

During meiosis, failure of chromosomes (ana I) or chromatids (ana II) result in gametes with extra or missing
chromosomes

During mitosis, failure of two chromatids of a single chromosome (anaphase) to separate, results in daughter
cells with extra or missing chromosomes. Results in mosaicism (a fraction of body cells have extra or
missing chromosome)

Polyploidy, all chromosomes undergo meiotic nondisjunction and produce gametes with 2n chromosome
count. Common in plants
Human Genetic Defects

Mutations – in somatic cells => tumors, in gametes => transmitted to offspring; insertion, deletion,
substitution; ex sickle-cell anemia

Aneuploidy- genome with extra or missing chromosome
o Ex: Down Syndrome (trisomy 21)
o Turner Syndrome (XO – caused by nondisjunction of the sex chromosome)
o Klinefelter (XXY)
Pyrimidines – CUT the PY; 1 ring
*Because G is triple bonded to C, higher G/C content more stable
*Nucleotides are H-bonded
Redundancy/ Degeneracy – genetic code synonyms, multiple codons for same AA
nucleoside = sugar+base
Protein Synthesis – Replication => Transcription => Translation

DNA synthesis occurs during S-phase. In G2 the cell prepares to divide. During G1, we see the
production of mitochondria, ribosomes, and much protein synthesis. Ribosomes are assembled by
the nucleolus.

Replication – DNA => DNA synthesized in 5’=>3’; helicase unwinds double helix and an RNA
polymerase called primase begins replication

Transcription – DNA => RNA (nucleus), mRNA has inverted complementary code, ex 5’ TCTTT
3’ mRNA would be 3’ AGAAA 5’ **principal site of the regulation of gene expression

Translation – RNA => Protein (cytoplasm); mRNA translated to AA
exons – nucleotide base sequences that are transcribed into mRNA  proteins; Introns – are removed during
transcription; (exons = don’t exit)
mRNA – carries complement of DNA from nucleus to ribosomes, least abundant RNA
tRNA – brings AA to ribosomes during synthesis, recognizes AA and codons; in cytoplasm; smallest form of RNA
rRNA – ribosomal RNA; most abundant form of RNA
Ribosomes – two subunits; three binding sites: 1 for mRNA, 3 for tRNA
PCR technique – makes multiple DNA copies in vitro
X-Ray diffraction = most accurate way to discover molecular structures.
Polypeptide sequence – initiation (AUG), elongation, termination (UGA UAG UAA)
Gene Regulation – transcription enables prokaryotes to control metabolism
Inducible system – require inducer for transcription

RNA polymerase binds to promoter => structural genes transcribed

Repressor binds to operator => structural genes NOT transcribed

Inducer binds to repressor => no binding to operator => genes transcribed
Repressible system – constant state of transcription unless corepressor- repressor complex present to inhibit
Bacteriophage – virus that infects host bacterium; attachment/ adsorption => penetration/ eclipse=> lytic or lysogenic
Lytic – phage DNA takes control of bacterium/ makes numerous progeny; bacterial cell bursts (lyses) releasing virons;
these types of bacteriophage are called virulent; ALL HOST cells destroyed = evolutionary disadvantage
Lysogenic – becomes integrated into genome in harmless way (provirus/prophage); cleverness is that every time the
host reproduces itself the prophage is reproduced too
Techoic acids – used for recognition and binding sites by bacterial viruses that cause infections
Chapter 4 – Embryology
Seven Major Steps During Embryonic Development (these are for sea urchin, but generally universal)
1. Fertilization
a. Recognition: acrosome of sperm meets vitelline layer (zona pellucida in humans) that ensure
fertilization by correct species
b. Penetration- fusing of plasma membranes
c. Formation of fertilization membrane by vitelline layer that blocks additional sperm
d. Completion of meiosis II in secondary oocyte, producing ovum(egg) and polar body
e. Fusion of nuclei and replication of DNA- formation of DIPLOID ZYGOTE
2.
Cleavage – rapid cell divisions without cell growth – each resulting cell (blastomere) contains less cytoplasm
than original zygote – increased surface area improves gas exchange
a. Embryo polarity- egg has upper, animal pole (small, rapidly dividing cells that give rise to three
primary germ layers) and lower, vegetal pole (large yolky cells that divide very slowlydifferentiates into extraembryonic membranes that protect and nourish embryo
b.
c.
d.
e.
3.
4.
5.
Polar and equatorial cleavages- Early cleavages are polar, dividing egg into segments that stretch
from pole to pole (like an orange). Other cleavages are parallel with equator
Radial and spiral cleavages- Deuterostomes (sea cucumbers, etc), early cleavages are radial. In
Protostomes, cleavages are spiral, forming cells on top that are “shifted”
Indeterminate and determinate cleavages
i. Indeterminate: produces blastomeres tha can individually complete development – often
results from radial cleavage of deuterostomes
ii. Determinate: developmental program limited – often results from spiral cleavage of
protostomes
Morula
a. Successive cleavage results in this solid ball of cells
Blastula
a. Cell division continues and liquid fills the morula, producing blastula. Center cavity is called the
blastocoel
b. In humans, blastocyst implants into endometrium
Gastrula
a. Deuterostomes (sea cucumbers, etc), early cleavages are radial and blastopore becomes anus. In
Protostomes, cleavages are spiral, forming cells on top that are shifted and blastopore becomes
mouth.
b.
c.
d.
e.
6.
7.
Endoderm – epithelial lining of digestive & respiratory, parts of liver, pancreas, thyroid, and
bladder lining
Mesoderm – musculoskeletal, circulatory system, excretory system, gonads, connective tissue,
portions of digestive & respiratory, notochord
Ectoderm – Nervous system (brain and spinal cord), integument (epidermis & hair / epithelium of
nose, mouth, anal canal), lens of eye, retina, teeth, neural tube
Extraembryonic membrane development – in birds, reptiles, and humans, called the amniotes, the
extraembryonic membrane develops as follows
a. Chorion: outer membrane. Birds and reptiles-membrane for gas exchange. Mammals, chorion
implants into endometrium, and later, the chorion and maternal tissue form the placenta (a blend of
maternal and embryonic tissues across which gases, nutrients, and wastes are exchanged)
b. Allantois- Sac that buds off from archenteron (cavity of gastrula forming primitive gut) that
eventually encircles the embryo, forming layer below chorion. Eventually forms umbilical cord,
transporting gases, nutrients, and wastes, and becomes urinary bladder in adults
c. Amnion- encloses amniotic cavity, cushions developing embryo, much like coelom cushions
internal organs in coelomates
d. Yolk sac- In birds and reptiles, yolk sac membrane digests enclosed yolk and blood vessels transfer
nutrients to embryo. In placental mammals, yolk sac is empty, as umbilical cord delivers nutrients
e.
Organogenesis – as cells continue to divide after gastrulation, they differentiate, and develop into specific
tissues and organs.
a. Notochord- cells along dorsal surface of mesoderm form notochord (stiff rod that provides support
in lower chordates. Vertebrae of higher chordates formed from nearby cells of the mesoderm
b. Neural tube- In ectoderm layer directly above notochord, layer of cells forms neural plate. Plate
indents, forming neural groove, then rolls up into a cylinder, the neural tube. This develops into
the CNS. Additional cells roll off top and form neural crest (which form teeth, bones, muscles of
skull, pigment cells in skin, and nerve tissue)
c.
Notable exceptions to the general embryonic development patterns
1. Frog
a. Gray crescent: Each individual cell could develop into normal frog onlyif it contained a portion of
gray crescent (results upon reorg. of cytoplasm upon sperm penetration
b. Gastrulation: formation of dorsal lip
c. Yolk: yolk is much more extensive, yolk plug near dorsal lip
2. Bird
a. Blastodisc- yolk of egg is extremely large, so cleavage occurs instead in blastula that consists of
flattened disc-shaped region called blastodisc
b. Primitive streak- Upon onset of gastrulation, invagination occurs along this line (rather than a
circle). This results in an elongated blastopore (as opposed to the circular blastopore found in sea
urchins and frogs)
3. Humans and most other mammals
a.
b.
c.
d.
Blastocyst- blastula stage (consists of outer ring, trophoblast, and inner cell mass
Trophoblast- outer ring of cells
i. Accomplishes implantation
ii. Produces human chorionic gonadotropin (HCG) to maintain progesterone production
of the corpus luteum
iii. Will later form the chorion
Embryonic disc-
i.
Within cavity created by trophoblast, bundle of cells called the inner cell mass, clusters at
one pole and flattens into embryonic disc which will undergo gastrulation and
organogenesis. Analagous to blastodisc of birds and reptiles. Gastrulation also occurs at
primitive streak.
Factors that influence cellular development
1. Influence of the egg cytoplasm- cytoplasmic material distributed unequally (think gray crescent in frogs and
yolk in bird eggs). This results in embryonic axes (animal and vegetal poles). Cleavage will thus result in
daughter cells with varying cytoplasmic material composition, and substances unique to certain cells may
influence development
2. Embryonic induction- influence of one cell or group of cells over neighboring cells. The controller cells are
called organizers. They act by secreting chemicals. EX: dorsal lip of blastopore induces development of
notochord in cells nearby
3. Homeotic genes- These genes turn on and off other genes that code for substances that directly affect
development. A gene segment called a homeobox identifies this particular class of genes (180bp, encodes
homeodomain of protein)
Labor (three stages)
1. Cervix thins out and dilates, amniotic sac ruptures and releases fluids
2. Rapid contractions followed by birth
3. Uterus contracts and expels umbilical cord and placenta
Chapter 5 – Vascular Systems in Plants and Animals
Circulation in Invertebrates

Protozoans (unicellular animal-like protists- movement of gas through simple diffusion within cell

Cnidarians – body walls 2 cells thick, therefore all cells in direct contact with either internal or external
environment. Ex- hydra

Arthropods- most insects and molluscs
o Open circulatory system- pump blood into internal cavity (hemocoel or sinuses), which bathe
tissues in oxygen and nutrient containing (hemolymph). This fluid returns to heart through holes
called ostia.

o
Annelids- earthworm
o Closed circulatory system- blood is confined to vessels.

Away from heart: aorta arteries  arterioles  capillaries

Back to heart: capillaries  venules  veins
Circulation in Humans

Cardiovascular system: four-chambered heart, network of blood vessels, and blood


Heart:
o
o
Fetal Heart
Right side pumps deoxygenated blood into pulmonary circulation (toward lungs)
Left side pumps oxygenated blood into systemic circulation (throughout body)

Cardiac cycle – regulated by autorhythmic cells (initiate contractions independently of nerve cells)
1. SA (sinoatrial) node, or pacemaker, initiates by contracting both atria and sending delayed
impulse to stimulate AV (atrioventricular) node.
2. AV node sends impulse through bundle of His, that results in contraction of ventricles
3. When the ventricles contract (systole phase), blood is forced through pulmonary arteries and aorta
– When they relax (diastole phase), backflow into ventricles causes semilunar valves to close.

Hydrostatic pressure from heart causes blood to move through arteries. Blood pressure drops as it reaches the
capillaries, and reaches near zero in the venules. Blood continues to move through veins not because of
contractions of the heart, but because of movements of adjacent skeletal muscles. Valves in the veins
prevent backflow.

Blood Vessels: (arteries, veins, and capillaries)
o Arteries: thick-walled, muscular, elastic, pump oxygenated away (except for pulmonary arteries
that transport deoxygenated blood from heart to lungs)
o Veins: Larger veins often have valves to aid in transport of deoxygenated blood back to heart due
to fighting gravity (except for pulmonary veins and umbilical vein that carry oxygenated blood)
o Capillaries: have smallest diameter- single layer of endothelial cells across which gases, nutrients,
enzymes, hormones, and waste diffuse

Lymph Vessels
o Lymphatic system is secondary circulatory system- transports excess interstitial fluids
o Transports interstitial fluid, (lymph), through the contraction of adjacent muscles.
o Valves prevent backflow- fluid returns to blood circulatory system through two ducts located in
shoulder region
o Lymph nodes contain phagocytic cells (leukocytes) that filter the lymph and serve as immune
response centers

Blood – 4-6 liters in the human body
o 55% liquid (plasma) and 45% cellular components – plasma is an aqueous mixture of nutrients,
salts, gases, wastes, hormones, and blood proteins (globins, albumin, fibrinogen
o Cellular components

Erythrocytes (RBCs) – transport O2 (up to 4) on hemoglobin, catalyze conversion of
CO2 and H2O to H2CO3 – lack nucleus to maximize hemoglobin content

Leukocytes (WBCs) – larger and phagocytize foreign matter and organisms

Diapedesis – the process by which WBCs become part of the interstitial fluid
(slip through the endothelial lining

Platelets- cell fragments involved in blood clotting – lack nuclei

Convert fibrinogen (inactive) to fibrin (active)

Derived from megakaryocytes
Process of blood clotting
1. Platelets contact exposed collagen of damaged vessel and cause neighboring platelets to form platelet plug
2. Both the platelets and damaged tissue release clotting factor, thromboplastin
3. Thromboplastin converts inactive plasma protein prothombrin to thrombin (active)
4. Thrombin converts fibrinogen into fibrin
5. Fibrin thredas coat damaged area and trap blood cells to form a clot
Hemoglobin – binds CO w/ much greater affinity than myoglobin
Myoglobin = single chain, stores O2 in muscle
Ductus venosus – allows blood to bypass the liver
Foramen ovale – allows blood to bypass pulmonary circulation by entering the left atria directly from the right atria
Ductus arteriosus – conducts some blood from the pulmonary artery to the aorta (bypassing the lungs)
Cardiac Output (CO) = SV (stroke volume) X HR (heart rate)

Stroke volume = volume of blood discharged from the ventricles with each contraction.

Cardiac output = volume discharged from ventricle each minute.

Stroke volume = end systolic volume – end diastolic volume.
Sodium-Calcium Channel – when open allow both Na+ & Ca2+ down gradient; stay open longer than fast sodium
channels; causing membrane depolarization to last longer in cardiac muscle
Intercalated disks – hold together adjacent cells of cardiac muscle, allow cardiac muscles fibers to transmit electrical
impulses rapidly (disks have low resistance to impulses)
Immune system – (three biological levels of defense)
1. Skin and mucous membranes – non-specific first line of defense
a. Skin-oily and acidic, pH of 3-5
b. Antimicrobial proteins (lysozyme) in saliva, tears, and other mucous membranes
c. Cilia- line lungs to sweep out invaders
d. Gastric juice- in stomach, kills most microbes
e. Symbiotic bacteria- in digestive tract and vagina outcompete damaging organisms
2.
Several nonspecific mechanisms- non-specific second line of defense
a. Phagocytes- leukocytes (WBCs) including neutrophils and monocytes (macrophages), and
natural killer cells
b. Complement- 20 natural proteins that “complement” defense. Attract phagocytes to foreign cells
c. Interferons- substances secreted by cells that stimulate neighboring cells to produce protective
proteins
d. Inflammatory response- series of non-specific events that occur in response to pathogens. EX:
when skin is damaged and bacteria enter the body
1. Histamine secreted by basophils (WBCs) in connective tissue
2. Vasodilation- stimulated by histamine, increases blood supply to area- increase in
temperature that stimulates WBCs and can kill pathogens
3. Complement- helps phagocytes engulf foreign cells, stimulate basophils to release
histamine, and help lyse foreign cells
3.
Immune Response- third line of defense targeting specific antigens
a. The major histocompatibility complex, MHC allows immune system to determine self and nonself
1. Collection of glycoproteins(proteins with carbohydrate) that exists on membranes of all
body cells – specific to individual
b. Lymphocytes (WBCs) – primary agents of immune response – concentrated in nodes, thymus
gland, and spleen
1. B cells- originate and mature in Bone marrow, and respond to antigens. Plasma
membrane has specific antigen receptors called antibodies (immunoglobins)

There are five classes: IgA, IgD, IgE, IgG, and IgM

When B cells encounter and bind antigens, they proliferate and produce both:
a. Plasma cells- release specific antibodies to circulate b. stream
b. Memory cells- long lived, do not release antibodies immediately,
instead respond quickly to subsequent invasion
2. T cells- originate in bone marrow, but mature in Thymus gland. Plasma membrane
contains antigen receptors for molecules displayed by nonself cells

When T cells encounter nonself cells, they proliferate and produce:
a. Cytotoxic (killer) T cells- recognize and destroy nonself cells by
lysing them
b. Helper T cells- stimulate proliferation of B cells and killer T cells
*The process of clonal selection- occurs when an antigen binds to B cell or a nonself cell binds to a T cell. The
“selected” B or T cells proliferate and produce identical clones of the parent cell.*
c.
Two types of Immune response
1. Cell-mediated response – uses mostly T-cells and responds to any nonself cell,
including cells invaded by pathogens by the following steps:

T cells produce killer T cells

T cells produce helper T cells

Helper T cells bind to macrophages

Helper T cells then produce interleukins- chemical communicators between
leukocytes that induce positive-feedback events resulting in proliferation of
interleukins, macrophages, helper and killer T cells, and B cells
2. Humoral (bodily fluid) response (anti-body mediated) – involves most cells and
responds to antigens or pathogens circulating in lymph or blood

B cells produce plasma cells

B cells produce memory cells

Macrophage and helper T cells stimulate B cell production

General progression: Naïve  Mature  Plasma  antibody
Ways humans have supplemented humoral defense
1. Antibiotics- chemicals derived from bacteria or fungi that are harmful to other microorganisms
2. Vaccines- substances that stimulate production of memory cells – artificially active immunity
3. Passive immunity- transferred antibodies from another individual- EX: newborns from mother
a. Acquired immediately, but short-lived and non-specific
b. Gamma globulin (blood containing antibodies) – can confer temporary protection against hepatitis
and other diseases
Rh factor – another antigen that can be present on red blood cells / + or -/ can lead to pregnancy issues if the mother
carries anti-Rh antibodies
Vascular Transport in Plants

Transport in plants must supply plant cells with nutrients and remove waste

Translocation – circulation in plants
o Plant stem is primary organ which contains vascular bundle
o Vascular bundle includes xylem, phloem, and cambium cells





Xylem- conduction of water and minerals UP stem, and mechanical support
o DEAD at maturity- essentially cell walls containing material transported
o Two types: tracheids (long and tapered, water travels through pits) and vessel elements (shorter
and wider and water travels through perforations- more efficient and more evolutionarily advanced)
o Rise of water explained by:

Transpirational pull- as water evaporates from leaves, vacuum pulls water up

Capillary action- liquid in thin tube rises due to surface tension of water and interactions
between liquid and tube

Root Pressure- water entering root hairs exerts pressure, pushing water up stem
Phloem- conduction of sugars DOWN stem- on outside of vascular bundle
o Made up of sieve-tube elements that form sieve tubes
o LIVING at maturity, but lack nuclei and ribosomes.
o Pores form sieve plates, where cytoplasm of two cells is in contact
o Companion cells adjacent and attached by plasmodesmata, maintain support for sieve tube
members
o EX: If a strip of bark is removed around trunk, phloem connections are severed and tree will die
Cambium – two layers thick; undifferentiated cells, give rise to xylem/ phloem; type of meristem
o Between the xylem and phloem, and cells differentiate according to proximity
Gross structure of Woody Stem
o Layers occur starting from the outside:
o epidermiscortexphloemcambiumxylempith
Root- absorbs materials through root hairs and anchors plant

o Root hairs increase surface area for absorption of water and minerals from soil
o Epidermiscortexphloemxylemcambium
Regions of Growth in the Plant
o Meristem- actively dividing, undifferentiated cells

Cambium- lateral meristem (provides lateral growth for plant)

Apical- located at roots and stems and provide vertical growth
o After dividing, the new cells elongate (zone of elongation) and differentiate
Chapter 6 – Endocrinology (Reference problem 90 from DESTROYER)
Hypothalamus- monitors external environment and internal conditions of the body; Contains neurosecretory cells
that link the hypothalamus to the pituitary gland. Regulation of the pituitary = negative feedback mechanisms and by
secretion of releasing and inhibiting hormones; secretes ADH (vasopressin) and oxytocin to be stored in posterior
pituitary; also secretes GnRH (gonadotropin releasing hormone), which stimulates anterior pituitary to secrete FSH
and LH
Anterior Pituitary- mainly regulates hormone production by other glands – itself regulated by hypoth.
1. Direct hormones: directly stimulate target organs
o Growth hormone (HGH)- stimulates bone and muscle growth
o Prolactin- stimulates milk production in females
o Endorphins- inhibit perception of pain
2. Tropic hormones: stimulate other endocrine glands
o Adrenocorticotrophic hormone (ACTH)- stimulates adrenal cortex  release glucocorticoidsinvolved in regulation of metabolism of glucose
o Thyroid-stimulating hormone (TSH)- stimulates thyroid gland to release thyroid hormone
o Luteinizing hormone (LH): females-stimulates formation of corpus luteum / males- stimulates
interstitial cells of testes to produce testosterone
o Follicle-stimulating hormone (FSH): females- stimulates maturation of ovarian follicles to secrete
estrogen / males- stimulates maturation of seminiferous tubules and sperm prod
Posterior Pituitary- does not synthesize hormones, stores ADH and oxytocin produced by hypothalamus
Antidiuretic hormone (ADH or vasopressin)- increases reabsorption of water by increasing
permeability of nephron’s collecting duct  water reabsorption and increased blood volume
Oxytocin- secreted during childbirth- increases strength of uterine contractions and stimulates milk
production
Pineal gland- secretes melatonin- plays role in circadian rhythm
Thyroid- located on ventral surface of trachea
Thyroxine (T4) and Triiodothyronine (T3)
o Derived from tyrosine and necessary for growth and neurological development in children and
increase metabolic rate in body
o Hypothyroidism- undersecretionlow heart rate and respiratory rate
Hyperthyroidism- oversecretion  increased metabolic rate and sweating

Both lead to GOITERS
Calcitonin (“tones down” Ca2+) in blood
o Decreases plasma Ca2+ by inhibiting its release from bone
Parathyroid- four pea-shaped structures on thyroid
Parathyroid hormone (PTH)- antagonistic to calcitonin
o Raises Ca2+ concentrations in blood by stimulating release from bone
o
Thymus- involved in immune response
Secretes thymosins that stimulate lymphocytes (WBCs) to become T-cells (identification and
destroying of infected body cells)
Adrenal gland- on top of kidneys and consist of:
Adrenal cortex
o Glucocorticoids (cortisol and cortisone)- raise blood glucose levels
o Mineralcorticoids (aldosterone)- increases reabsorption of Na+ and excretion of K+

Causes passive reabsorption of water in nephron rise in blood volume/pressure
o Cortical sex hormones (androgens=male sex hormones)- effect is small due to testis
Adrenal medulla
o Epinephrine and Norepinephrine (adrenaline and noradrenaline)- “fight or flight”

“fight or flight”(sympathetic N.S.)

glycogenglucose, constricts blood vessels, increased heartbeat
Pancreas- both exocrine and endocrine
Glucagon (secreted by α “active”)- glycogenglucose
Insulin (secreted by β “bumming”)- glucose  glycogen
somatostatin
Testis- testosterone- spermatogenesis, secondary sex characteristics
OvariesEstrogen- menstrual cycle, secondary sex characteristics
Progesterone- menstrual cycle, pregnancy
Gastrointestinal hormones
Gastrin- food in stomach, stimulates secretion of HCl
Secretin- small intestine- when acidic food enters from stomach  neutralize acidity of chime by secretion of
alkaline bicarbonate
Cholecystokinin- small intestine- presence of fats  causes contraction of gall-bladder and release of
bile(involved in digestion of fats)
Endocrine – synthesize and secretes hormones into bloodstream
Exocrine – secrete substances into ducts (ex. gall bladder)
Apocrine gland – gland that responds to stress (ex. sweat glands)
Eccrine gland – gland responsible for maintenance of body temperature (ex. sweat glands)
Peptide Hormones
synthesized into the rough ER & modified in the Golgi; cannot cross mem
surface receptors
typically act via secondary messengers (ex: cyclic AMP)
Steroid Hormones
synthesized from cholesterol in smooth ER; hydrophobic = freely diffuse
intracellular receptors
hormone/receptor binding to DNA promotes specific transcription
Bind to cytosolic protein, the complex enters the nucleus and binds to receptors on chromatin
Hormonal Regulation in Plants
Auxins – associated with growth patterns
1. Phototropism- tendency of plants to grow toward light
a. Auxin (indoleacetic acid) supply to side receiving light reduced  slowed growth
2. Geotropism- tendency of plants to grow toward or away from gravity
a. Horizontally placed plant will grow up (uneven distribution of auxin) – negative
b. Horizontal roots feel opposite effect and grow down(more auxin less growth in this case) positive
3. Inhibition of lateral buds
a.
Auxins produced at terminal bud of growing tip move downward in shoot and inhibit
development of lateral buds. At the same time, initiate formation of later roots
Gibberellins – stimulate rapid stem elongation, inhibit formation of new roots, terminate dormancy of seeds and buds
Kinins – promote cell division
Ethylene – stimulates fruit ripening and senescence (aging)
Inhibitors – block cell division and serve role in growth regulation – maintenance of dormancy in lateral buds and
seeds during autumn and winter, degraded over time or by cold (ex: abscisic acid)
Anti-auxins – regulate activity of auxins
Chapter 7 – Neuroscience
Neuron – consists of several dendrites, single axon and cell body
Dendrites – receive information and transfer it TO CELL body
Axon – transfers impulses AWAY from cell body
Glial Cells – produce myelin

Oligodendrocytes – produce myelin in CNS

Schwann – produce myelin in PNS. Schwann cells act as insulators and are separated by nodes of
Ranvier. Instead of traveling continuously down axon, action potential jumps from node to node
(salutatory conduction), speeding up impulse
Three types of neurons:
1. Sensory (Afferent)- receive initial stimulus (Ex: neurons in retina of eye) ABRAIN
2. Motor (Efferent)- stimulate effectors, target cells that elicit some response (Ex: neurons may stimulate
the muscles, sweat glands, or cells in the stomach to secrete gastrin. BRAIN  M
3. Association (Interneuron)- located in spinal cord & brain- receive impulses from sensory and send
impulses to motor neurons. They are integrators, as they evaluate impulses for appropriate response
Transmission of a nerve impulse:
***The membrane of an unstimulated neuron is polarized, although a high concentration of Na+ is present outside the
cell and a high concentration of K+ is present inside the cell (the inside is actually negative due to the negatively
charged proteins and nucleic acids residing in the cell). Additionally, neuron membranes are selectively permeable to
K+ as opposed to Na+, which helps to maintain the polarization.***
1.
2.
3.
4.
5.
Resting potential. Normal polarized state of neuron, -70 mV.
Action potential. Stimulus  gated ion channels let Na+ into the cell, depolarizing it. If the threshold level
is reached (-50mV), it will cause an action potential that will result in opening of Na+ channels down the
entire length of the neuron. All or nothing event!
Repolarization. In response to Na+ flow in, more gated ion channels let K+ out of the cell, restoring
polarization- but the Na+ are IN and the K+ are OUT
Hyperpolarization. By the time the channels close, too much K+ is released (-80 millivolts)
Refractory period. Neuron will NOT respond to new stimulus until Na+/K+ pumps return the ions to their
resting potential locations (outside/in, respectively)
Transmission across synapse- presynaptic cell  postsynaptic cell
I. Electrical- action potential travels along membranes of gap junctions (less common)
II. Chemical- most typical in animal cells
1. Ca2+ gates open- depolarization allows Ca2+ to enter the cell
2. Synaptic vessels release neurotransmitter- influx causes release into cleft
3. Neurotransmitter binds with postsynaptic receptors. Diffusion and binding
4. Postsynaptic membrane is excited or inhibited. Two possible outcomes:
i. Na+ gates open, membrane is depolarizedexcitatory postsynaptic potential (EPSP), if
threshold potential is succeeded, action potential is generated
ii. K+ gates open, membrane becomes hyperpolarized inhibitory postsynaptic potential
(IPSP)… it becomes more difficult to generate action potential
5. Neurotransmitter is degraded and recycled. Broken down by enzymes in cleft and recycled
Some common neurotransmitters
1. Acetylcholine- secreted at neuromuscular junctions  muscle contraction/relaxation
a. parasympathetic nervous system
2.
Epinephrine, norepinephrine, dopamine, and serotonin- secreted between neurons of CNS
a. sympathetic nervous system
3.
Gamma aminobutyric acid (GABA)- inhibitory neurotransmitter among brain neurons
**Greater diameter & more heavily myelinated axons will propagate faster impulses
** Synaptic vesicles fuse w/ presynaptic membrane => neurotransmitter => postsynaptic
** Neurotransmitter may be taken back into nerve terminal, degraded by enzymes in synapse, or diffuse out of the
synapse
Central Nervous System (CNS) – consists of the brain and spinal cord
Brain – outer grey matter (cell bodies) and inner white matter (axons); forebrain, midbrain, hindbrain
Forebrain – contains cerebral cortex (processes sensory input / important for memory and creative
thought), olfactory bulb (smell), thalamus (relay for spinal cord and cerebral cortex), hypothalamusvisceral function (water balance, blood pressure, and temp regulation, hunger, thirst, sex)
Midbrain – relay center for visual/ auditory impulses; motor control
Hindbrain – posterior part of brain; cerebellum (maintenance of balance, hand-eye coord, timing of rapid
movements), pons (relay center to allow communication b/w cortex and cerebellum), medulla oblongata
(breathing, heart rate, gastrointestinal activity) o These three together constitute the brain stem
Spinal cord- out white/inner gray(cell bodies). Sensory info enters through dorsal horn. All motor info exits through
the ventral horn.
Peripheral Nervous System (PNS) – somatic and autonomic nervous systems

Somatic – responsible for VOLUNTARY movement of skeletal muscles

Autonomic – involuntary movement; innervates cardiac and smooth muscle
o Sympathetic – fight or flight (higher BP and HR)
o Parasympathetic – rest and digest; non-emergency (lower HR, digestion, relaxation,
sexual arousal)
***A reflex arc is a rapid, involuntary response to a stimulus involving two or three neurons, but brain DOES NOT
integrate the sensory and motor activities… instead synapse in spinal cord***
Ex: Knee-jerk (patellar) reflex
Eye – cornea (focuses light) => pupil (diameter controlled by iris {pigmented}) => lens (controlled by cilliary
muscles) => retina
Cones: high-intensity illumination; sensitive to color
Rods: low intensity; important in night vision
- Fovea: densely packed with cones; important for high acuity vision
Myopia – nearsightedness
Hyperopia – farsightedness
Astigmatism – irregularly shaped cornea
Cataracts – lens becomes opaquelight cannot enter
Glaucoma – increase in pressure of eye due to blocking of outflow of aqueous humor
Ear – outer, middle and inner ear; transduces sound energy into impulses

Outer ear – auricle and auditory canal

Middle ear – amplifies sound; tympanic membrane (eardrum) vibrates at same frequency as
incoming sound => ossicles (malleus, incus, and stapes)

Inner Ear – vestibular apparatus (equilibrium) and cochlea (vibration of ossicles ecert pressure on
fluid stimulating hair cells in basilar membrane => action potential)
Chapter 8 – Respiration
Glucose Catabolism – oxidative breakdown of glucose; two stages are glycolysis and respiration
Glycolysis – breakdown of 1 glucose => 2 pyruvate in CYTOplasm

Glucose+2ADP+2Pi+2NAD+  2Pyruvate + 2ATP + 2NADH + 2H +2H20

Phosphofructokinase (step 3) – rate determining step; ATP consumed

Step 4 where fructose splits into 2 PGAL molecules
Fermentation – anaerobic conditions; NAD+ must be regenerated; produces only 2ATP per glucose
Cellular Respiration – can yield 36-38 ATP; O2 is final acceptor // PDC, CAC, ETC

PDC – mito MATRIX; CO2 is lost; NAD+ reduced to NADH

Citric Acid Cycle – Krebs cycle

2Acetyl-CoA +6NAD++2FAD+2GDP+2Pi+ 4H2O 4CO2 + 6NADH + 2FADH2 + 2ATP + 4H
+2CoA

ETC – also called OXIDATIVE phosphorylation INNER mito MEMbrane; electrons transferred
from NADH and FADH2 to oxygen; cytochromes are the carrier molecules with Fe in functional
unit (resemble hemoglobin)
Eukaryotic ATP production / glucose
*glycolysis (6 ATP)
2ATP invested
-2 ATP
4ATP generated
+4 ATP
2NADH X 2
+4 ATP
*PDC (pyruvate decarboxylation) (6 ATP)
2NADH X 3
+6 ATP
*CAC (24 ATP)
6NADH X 3
+18 ATP
2FADH2 X 2
+4 ATP
2GTP(ATP) X 1
+2 ATP
_________
TOTAL
+36 ATP
Mitochondrian:
1.
2.
3.
4.
Outer membrane: phospholipid bilayer
Intermembrane space: accumulation of H+ ions
Inner membrane: convolutions called cristae, where oxidative phosphorylation occurs
a. ATP synthase: phosphorylates ADP-ATP
Matrix: fluid filling area inside inner membrane. Krebs cycle & PYR Acetyl-CoA
**When glucose runs low, body utilizes the following in order: other carbs (glycogen in liver), fats (adipose tissue in
form of triglyceride) – hydrolyzed by lipases into fatty acids and glycerolPGAL(glycolytic intermediate), proteins
(only when carbs and fats gone) – each first converted to either glucose or glucose intermediates, which are degraded in
the glycolytic pathway and Citric Acid Cycle
** Fats are stored in adipose tissue as triglyceride / hydrolyzed by lipases to fatty acids / carried by blood to tissues/
must be activated / GREATEST ATP yield, even though glycogen stored can meet short term energy needs /
synthesized in cytosol / B-oxidation in mitochondrial matrix.
Cori cycle – converts lactic  pyruvate  glucose
Glyoxylate cycle occurs in plants & bacteria. Acetyl-CoA  succinate  carbohydrates
Invertebrate Respiration:

Cnidaria: Protozoa and Hydra
o Every cell in contact with water, and respiratory gases are exchanged btw cell and environment by
simple diffusion

Annelids:
o Mucus secreted by earthworm provides moist surface for gaseous exchange by diffusion
o Circulatory system bring O2 to cells and waste products (CO2) back to skin for excretion
o
o

Arthropods (80% of all living species – insects, spiders, crustaceans (crabs), etc…
o
Grasshopper
 Series of respiratory tubules called trachae open to surface in openings called
spiracles… no oxygen carrier is needed due to direct distribution and removal of
respiratory gaese between air and body cells by diffusion
o


Spider

Book lungs: stacks of flattened membranes enclosed in internal chamber
Fish
o
Water enters mouth, passes over gills, exits through operculum (gill cover). Countercurrent
exchange between opposing movements of water and underlying blood maximizes diffusion of O2
into blood and CO2 into water
Plant Respiration

Photosynthesis only takes place during the day.
o Photosynthesis produces glucose and gives off oxygen
o While respiration requires oxygen to degrade glucose

Plants undergo aerobic respiration similar to animals
o Glucose  2ATP + 2 pyruvic acid
o Gases diffuse into air space by entering and leaving through stomata of leaves or lenticels in
woody stems
o Anaerobic respiration takes place in simple plants when molecular oxygen is lacking
Human Respiration

Alveoli – where gas exchange between the circulatory system and the lungs occurs; surfactant reduces the
surface tension
1. Nose, pharynx (throat), larynx(voice box)
2. Trachea (epiglottis covers the trachea during swallowing)
3. Bronchi, Bronchioles: Two bronchi, which enter the lungs and branch into narrower
bronchioles
4. Alveoli: Each bronchiole branches ends in these small sacs, which are surrounded by bloodcarrying capillaries
5. Diffusion between alveolar chambers and blood: Gas exchange across moist, sac membranes
of alveoli. O2 diffuses through alveolar wall, through pulmonary capillary wall, into blood,
and into red blood cells. (CO2 is opposite)
6. Bulk flow of O2: O2 transported through body within hemoglobin containing red blood cells
(RBCs)
7. Diffusion between blood and cells: Oxygen diffuses out of RBCs, across blood capillary walls,
into interstitial fluids, and across cell membranes (CO2 opposite)
8. Bulk flow of CO2: CO2 mainly transported as HCO3- ions in plasma, liquid portion of blood.
Produced by carbonic anhydrase in RBCs. CO2 can also directly mix with plasma (as CO2
gas), or bind hemoglobin inside RBCs
9. Bulk flow of air into and out of the lungs:
a. Inhalation – diaphragm (under lungs) and intercostal muscles (btw ribs) contract/
flattens; increase in volume / decrease in pressure in lungs  bulk flow of air into
lungs.
b. Exhalation – passive process; decrease in lung volume/ increase in air pressureair
rushes out; diaphragm relaxes and expands

Bohr effect – hemoglobin O2 binding affinity decreases under conditions of low pH (high CO2 & [H+])
 oxygen loads released by hemoglobin

Decrease in CO2 or increase in pH will result in hemoglobin binding more O2

Result of: CO2 + H2O
H2CO3
H+ + HCO3−
*Oxygen diffuses from alveolar air into blood, CO2 diffuses from blood into lungs

Human respiration controlled by medulla oblongata

When ppCO2 increases, medulla stimulates increase in rate of ventilation
Chapter 9 – Autotrophic Nutrition
Stroma- fluid material that fills area inside inner membrane; Calvin cycle (dark reactions) occurs here
Chloroplast – plastid containing chlorophyll pigment and thylakoid membranes; photosynthesis
Thylakoids – the network of thylakoid membranes contains the protein complexes (including PSI and PSII) high H+
w/i during chemiosmosis

Stack of thylakoids called granum –
Lumen: H+ ions accumulate here during chemiosmosis (production of ATP during light reactions)
Photosystem – light capturing unit of the thylakoid; center is single chlorophyll
Photosynthesis – involves reduction of CO2 to carb and release of O2 from water; net reaction is reverse of respiration

6CO2 + 6H2O + light  C6H12O6 + 6O2
Noncyclic and Cyclic Photophosphorylation (light reactions) – convert solar energy to ATP and NADPH and occur
in the grana

Noncyclic – KEY pathway; high-energy electrons are transferred to electron acceptor NADP+; net
result is production of NADPH and ATP / photolysis of water:
H2O + ADP + Pi + NADP+ + light  ATP + NADPH + O2 + H+

Photosystem II: Electrons trapped by P680 in PSII are energized by light.

Primary e- acceptor: Two energized e- are passed to primary electron acceptor

Electron transport chain: Involves the carriers ferrodoxin and cytochrome, which contain
iron. Analogous to oxidative phosphorylation.

Phosphorylation: 2 e- move “down” ETC and lose energy. Energy lost is used to
phosphorylate 1.5 ATP molecules

Photosystem I: ETC terminates with PS I (w/ P700). The e- pair again is energized by sunlight
and passed to a different primary electron acceptor

NADPH: The 2 e- pass through short ETC, and produce NADPH

Splitting of Water: The two e- that originated in PS II are incorporated into NADPH. These elost are replaced by: H20  2H+ + ½ O2 + 2e
The e- go to PSII, one H+ will be used to form NADPH, and the ½ O2 contributes to
oxygen gas released

Cyclic e- flow – series of redox reactions returns electrons to PSI (w/ P 700) instead of incorporating them
into NADPH; ATP prod

1 ATP yielded
Chemiosmosis in thylakoid of chloroplasts:
1) H+ ions accumulate inside thylakoids: H+ released into the lumen of thylakoid when H2O is split, and are
carried from stroma into lumen by cytochrome btw PSII and PSI
2) pH and electrical gradient created across thylakoid membrane
a. H+ accumulate in lumen and pH decreases (pH=5), while pH increases in stroma (pH=8); this
creates a 1000 fold [H+] differential and a voltage gradient
3) ATP synthases generate ATP
a. H+ flow through ATP synthase out into stroma. 3H+ are required to generate 1ADP1ATP
4) Calvin cycle produces G3P using NADPH and CO2 and ATP
a. At end of ETC, after PSI, e- combine with NADP+ to form NADPH.
b. NADPH, ATP, and CO2 are then used to produce 2 G3P, and eventually glucose or other
carbohydrates
Dark Reactions – Calvin Cycle (occurs in stroma) –

Cannot occur in the absence of light, because it is dependent on ATP and NADPH from
photophosphorylation (light reactions)

use ATP and NADPH to reduce CO2 to carbs (CO2 fixed to RuBP –)

product is three carbon PGAL; six turns of the cycle (6 CO2 and 6 RBP) = 12 PGAL; 12PGAL can be
converted to 1 glucose + 6RBP; G3P = prime end product (immediate food nutrient)

6CO2 + 18ATP + 12NADPH + H+  18ADP + 18Pi + 12 NADP+ + C6H12O6
Key Steps of Dark Reaction (Calvin cycle): also known as C3 photosynthesis because PGA is 3 carbon
1. Carboxylation: 6CO2 + 6 RuBP  12 PGA (phosphoglycerate)
2.
Reduction: 12ATP and 12 NADPH used to convert 12 PGA  12 G3P
a.
3.
G3P is energy rich, and ADP, Pi, and NADP + sent back to light reactions
Regeneration: 6ATP used to convert 10G3P to 6RuBP
a. Allows these regenerated 6 RuBP to combine with 6 new CO2
4.
Carbohydrate synthesis:
a. 2 remaining G3P used to build glucose (and eventually starch and/or cellulose if needed)
*** Look in Cliffs for pathways***
Photorespiration: rubisco also fixes O2 in addition to CO2, a process called photorespiration; peroxisomes in close
proximity to chloroplasts are used to break down the products of O2 fixation
Leaf – site of photosynthesis; several adaptations for efficiency

Waxy Cuticle – reduce transpiration and conserve water
o Casparian strip – waxy band in plants that aid in water control

Palisade: layer of elongated chloroplast-containing cells over large SA, under upper epid.

Spongy Layer – moist surface necessary for diffusion of gases (also contain chloroplasts)

Guard Cells – surround stomata and control its size; open during day because the cells contain
chloroplasts which produce glucose; high glucose content causes high turgor and opening of
stomata

Vascular bundles: bring water to leaf from roots (xylem) and carry manufactured food out of leaf
(phloem)
Nitrifying Bacteria – oxidize ammonia and nitrites to nitrates and use the energy to make glucose; plants use the
nitrates to make proteins. Bacteria use the energy from the oxidation to make glucose
Chapter 10 – Muscles and Locomotion
Unicellular locomotion
Protozoans & primitive algae – cilia or flagella by means of power stroke and recovery stroke

Amoeba – extend pseudopodia; advancing cell membrane extends forward
Invertebrate locomotion

Hydrostatic skeletons
Flatworms – bi-layered muscles, longitudinal and circular, contract against hydrostatic skeleton
o Contraction causes hydrostatic skeleton to flow longitudinally, lengthening animal
Segmented worms (Annelids) – advance by action of muscles on hydrostatic skeleton
o Bristles in lower part of each segment, setae, anchor worm in earth while muscles push ahead

Exoskeleton
Arthropods – insect exoskeletons composed of hard chitin, necessitates molting for growth
Vertebrate Skeleton- comprised of an endoskeleton. Two major components are cartilage and bone
1. Cartilage – connective tissue; softer and more flexible; (ex: ear, nose, larynx, trachea, joints)
o from mesenchyme tissue  chondrocytes  produce collagen (present in tissue as triple
helix with hydroxyproline and hydroxylysine, ground substance, & elastin fibers
2. Bone – connective tissue; hard and strong, while elastic and lightweight
o Compact bone- dense bone that does not appear to have cavities; bone matrix is deposited in
osteons (Haversian systems) with a central microscopic channel called a Haversian canal
surrounded by concentric circles of bony matrix called lamellae
o Spongy (Cancellous) bone- less dense and consists of an interconnecting lattice of bony
spicules (trabeculae); filled with red / yellow bone marrow; (yellow = adipose  inactive)
o ***Bone growth occurs at cartilaginous epiphyseal plates
3.
Osteocytes
o OsteoBLASTS- build bone; do NOT carry out mitosis
o OsteoCLASTS- destroy bone “bone resorption”
Bone Formation – during FETAL stage of development
o Endochondral ossification- cartilagebone (EX: long bones; limbs, fingers, toes)
o Intramembranous ossification- undifferentiated connective tissue replaced by bone

(EX: flat bones; skull, sternum, mandible, clavicles)

Growth occurs at epiphyseal plates
Organization of Vertebrate Skeleton
Axial skeleton – basic framework (skull, vertebral column, rib cage)
Appendicular skeleton – bones of appendages, pectoral and pelvic girdles
Bone organization
o Sutures – immovable joints (ex: bones of skull)
o Moveable joints – bones that move relative to each other

Ligaments – bone-to-bone connectors; strengthen joints

Tendons- muscle-to-bone; bend skeleton at moveable joints
o Origin – point of attachment of muscle to stationary bone
o Insertion – point of attachment of muscle to bone that moves
o Extension = straightening of joint
o Flexion = bending of joint
4.
Muscular system- consists of contractile fibers held together by connective tissue
1. Skeletal muscle (striated muscle) – voluntary movement, fibers are multinucleated cells
a.
b.
c.
d.
e.
f.
Myofibrils – filaments divided into sarcomeres
Sarcomeres – individual contractile units
Sarcoplasmic reticulum – stores Ca2+; surrounds myofibrils
Sarcoplasm – cytoplasm
Sarcolemma – cell membrane; can propagate action potential
i. Connected to T-tubules- channels for ion flow
Mitochondria – present in large amounts in myofibrils
Joint types –
1. Fibrous – connect bones without allowing any movement (Ex: skull, pelvis, spinous process and
vertebrae)
2. Cartilaginous – bones attached by cartilage, allow little movement (Ex: spine and ribs)
3. Synovial – allow for much more movement; most common; filled with synovial fluid (Ex: carpals, wrist,
elbow, humerus & ulna, shoulder and hip joints, knee joint)
Sarcomere – is composed of thin filaments (actin) and thick filaments (myosin)
Z line – boundary of a single sarcomere; anchor thin filaments
M line – center of sarcomere
-
I band – region containing thin filaments (actin) only (on ends, only purple above)
H zone – region containing thick filaments (myosin) only (in middle, only green above)
A band – actin and myosin overlapping
o H and I reduce during contraction, while A does NOT
Contraction –
Stimulation Process of Sliding Filament Model – “all-or-nothing” response
1. Action potential of neuron releases acetylcholine when meets neuromuscular jxn
2. Action potential then generated on sarcolemma and throughout T-tubules
3. Sarcoplasmic reticulum releases Ca2+
4. Myosin cross bridges form – result of Ca2+ binding to troponin on actin helix
Sliding Filament Model
1. ATP binds to myosin head – converted to ADP + Pi, which remain attached to head
2. Ca2+ exposes binding sites on actin – binds troponintropomyosin exposes attachment sites
3. Cross bridges between myosin heads and actin filaments form
4. ADP + Pi are released  sliding motion of actin bring Z lines together (contraction)
5. ATP causes cross bridges to unbind – new phosphorylation breaks cross bridge
*Without new ATP, the cross bridges remain attached to myosin head… this is why corpses are stiff*
**Strength of contraction of single muscle fiber cannot be increase, but strength of overall contraction can be increased
by recruiting more muscle fibers**
Types of Muscle Response
A) Simple Twitch – response of a single muscle fiber to brief stimulus; latent, contraction, relax
1. Latent period – time btw stimulation and onset of contraction; lag
o Action potential spreads on sarcolemma and Ca2+ ions released
2. Contraction
3. Relaxation (absolute refractory period) – unresponsive to stimulus
B) Summation and Tetanus –
a. Summation – contractions combine and become stronger and more prolonged
b. Tetanus – continuous contractions; muscle cannot relax; will release if maintained
C) Tonus – state of partial contraction; muscle never completely relaxed
Smooth Muscle – involuntary movement, ONE central nucleus; LACK striation; stimulated by autonomic nervous
system (EX: lining of bladder, uterus, digestive tract, blood vessel walls, etc)
Cardiac Muscle – striated appearance (sarcomeres); myogenic (contraction independent of nerve cells); one or TWO
central nuclei
Chapter 11 – Digestion
Digestion in Unicellular Organisms

Amoeba
o Food capture: phagocytosisfood vacuoles
o Food vacuoles fuse with lysosomes

Paramecium
o Cilia sweep food into cytopharynx
o Food vacuole forms and moves toward anterior end of cell

Digestion in Invertebrates

Physical breakdown – cutting and grinding in mouth; churning in digestive tract

Chemical breakdown – enzymatic hydrolysis  smaller nutrients  pass through semi-permeable membrane
of gut cells to be further metabolized

Cnidarians
o Hydra- intracellular and extracellular digestion


Annelids
o Earthworms – one-way digestive tract

Crop – food storage

Gizzard – grind food
 Intestine – contains typholosole to increase surface area for absorption
o

Arthropods
o
Also have jaws for chewing and salivary glands
o
Digestion in Humans
Four groups of molecules encountered
1. Starches  glucose
2. Proteins  amino acids
3. Fats  fatty acids
4. Nucleic acids  nucleotides
Digestion follows a specific series of events
***Note – All digestive enzymes cleave SPECIFIC bonds
1. Mouth - salivary amylase breaks down (starchmaltose), bolus is swallowed
2. Pharynx (throat) – epiglottis, flap of tissue, blocks trachea so only solid and liquid enter…
3. Esophagus – tube leading to stomach, food travels by contractions (peristalsis)
4.
Stomach – secretes gastric juice (digestive enzymes and HCl)
a. Storage – accordion-like folds allow 2-4 liters of storage
b. Mixing – mixes food w/ H2O and gastric juice  chyme (creamy medium)
c. Physical breakdown – muscles break food; HCl denatures proteins & kills bacteria
d. Chemical breakdown – pepsin (secreted by Chief cells) digests proteins; (pepsinogen activated by
HCl, which is secreted by parietal cells)
i. Peptic ulcers – caused by failure of mucosal lining to protect stomach
e. Controlled release – chyme  small intestine; controlled by pyloric sphincter
5.
Small intestine – first 25cm (duodenum), continues breakdown of starches and proteins as well as
remaining food types (fats and nucleotides); ileocecal valve between it and large intestine
a. Enzyme origin
i. Small intestine – proteases, maltase and lactase, phosphatases (nucleotides)
ii. Pancreas – trypsin & chymotrypsin (proteases), lipase, pancreatic amylase
–
These enzymes in alkaline solution (pancreatic duct  duodenum)
iii. Liver – bile (emulsifies fats) stored in gall bladder, flows through bile duct
b. Remainder of small intestine (6m) absorbs breakdown products (villi and microvilli)
i. Amino acids and sugarscapillaries ; fatty acids and glycerol  lymph. system
6.
Large intestine (colon) – reabsorption of water and salts to form feces; 1.5m long
a. Feces stored at end of L.I. in the rectum  excreted through anus
b. At beginning is appendix, which in herbivores is large cecum (cellulose digestion) with the help of
bacteria
c. Bacteria in large intestine = main source of vitamin K
Hormones involved in the digestive process
1. Gastrin – produced by stomach lining when food reaches or upon sensing of food; enters blood stream and
stimulates other stomach cells to produce gastric juices – secreted by G-cells
2. Secretin – produced by cells lining duodenum when food enters; stimulates pancreas to produce
bicarbonate, which neutralizes the chyme
3. Cholecystokinin – produced by S.I. in response to fats; stimulates gallbladder to release bile and pancreas to
release its enzymes
Digestion in plants and fungi
***Plants have no digestive system, but intracellular processes similar to animals do occur***
Intracellular digestion – store primarily starch in seeds, stems, and roots; when nutrients are required, polymers are
broken down (into glucose, fatty acid, glycerol, and amino acids) by enzymatic hydrolysis
Extracellular digestion – several plants must obtain nutrient from environment


Fungi – rhizoids of bread mold, secrete enzymes into bread, producing simple digestive products which are
then absorbed by diffusion into rhizoid
Venus flytrap – enzymes digest trapped fly (serves as nitrate source); ***still autotrophic**
START - ALANS NOTES ON DIGESTIVE SYSTEM
pharynx – where food and air passages cross
Goblet Cells – specialized epithelial cells that secrete mucous
Stomach – churning produces acidic semi-fluid mixture called chyme; secretes pepsin and HCl (activates certain
proteins and kills bacteria)
Pepsin (pepsinogen) – protein hydrolyzing enzyme; secreted by chief cells
parietal cells – secrete HCL, intrinsic factor (B-12 absorption)
mucous cells – secrete protective mucous
G-cells – secrete the hormone gastrin which stimulate the HCL production of parietal cells; innervated by
vagus nerve, found w/i gastric glands of stomach
Cholecytoskinin (CCK) = hormone made by cells of duodenum, stimulates bile release
Enterogastrone – produced in the duodenum; inhibits stomach gland secretion and slows stomach’s muscular
movement when fatty food is in the intestine (more time for digestion)
Small Intestine – chemical digestion completed here; duodenum, jejunum, ileum; villi are used for absorption (contain
capillaries and lacteals) / active absorption (glucose, AA) and passive

Most digestion done in duodenum – secretes secretin which causes pancreas to secrete buffer
(HCO3- )0 secretions of intestinal glands, pancreas, liver and gall bladder mix

Intestinal mucosa secretes lipases (fat digestion), aminopeptidases (polypeptide digestion), and
disacchiridases (breakdown of maltose, lactose, sucrose)

Portal vein – directs glucose and other monosaccharides to the liver from the intestinal tract
Liver – albumin synthesis, bile production, destruction of worn-out old red blood cells, converts nitrogenous waste into
urea, glycogen storage
Bile – emulsifies fat; contains no enzymes; exposes greater surface area of fat to lipases
Pancreas – produces amylase (carb digestion), trypsin (protein digestion), and lipase (fat digestion); secretes
BICARBONATE juice that neutralizes chime; acts as a endocrine and exocrine gland
–
Endocrine pancreas – glucagon, insulin, and somatostatin (suppresses the release of gastrointestinal
hormones such as gastrin, secretin and cholecystokinin  decrease the rate of gastric emptying
along w/ reducing blood flow w/in intestines.
Chapter 12 – Excretion
Protozoans and Cnidarians – all cells in contact with external, aqueous environment
Water soluble wastes (ammonia, CO2) exit by simple diffusion
Paramecium – possesses contractile vacuole for XS H2O excretion by active transport
Annelids – CO2 excretion directly through moist skin
- Nephridia in each body segment excrete water, salts, and urea
Platyhelminthes – flame cells (protonephridia)
- Body fluids filtered across flame cells, whose cilia move fluids through tube system
Arthropods – CO2 released from tissues  tracheae (which are continue with ext. air thru spiracles)
Nitrogenous wastes – uric acid crystals (H2O conservation)
o Accumulate in Malphigian tubules, then are transported to intestine for excretion
o
Excretion in Humans – lungs, liver, skin, and kidney
Lungs – CO2 and H2O(g) diffuse from blood and are continually exhaled
Liver – processes nitrogenous wastes, blood pigment wastes, other chemicals, UREA prod.
Skin – sweat glands in skin excrete water and dissolved salts/regulate body temp.
- Kidney – Three regions: 1) outer cortex, 2) inner medulla, and 3) renal pelvis
-
-
o
1 million nephrons each
Nephrons – composed of renal corpuscle and renal tubule; reabsorbs nutrients, salts, and water

Renal corpuscle – glomerulus (sieve) surrounded by Bowman’s capsule; afferent arteriole=into
glomerulus; efferent arteriole=out of glomerulus

Renal tubule –
o Proximal convoluted tubule – active reabsorption of glucose, ions, amino acids begins
o Loop of Henle (majority of nephron)

DESCENDING – only permeable to water

ASCENDING makes renal medulla salty–actively pumps out Na+,K+,Cl
This process allows reabsorption of 99% of filtrate  conc. urine
o Distal convoluted tubule – more reabsorption of glucose, ions, water, etc.
o Collecting duct – collects remaining waste products and unneeded water

Returns to medulla (salty part), where antidiuretic hormones (ADH /
vasopressin) can make MORE water leave from urine by increasing
permeability of collecting duct  urine even more concentrated
Urine Formation – filtration, secretion, and reabsorption

Filtration – fluid that goes through glomerulus (afferent arteriole => glomerulus => efferent) to the
rest of the nephron is called filtrate; particles that are too large to filter through (blood and albumin)
remain in circulatory system; passive process; driven by hydrostatic pressure of blood

Secretion – substances such as acids, bases, and ions (K+) are secreted by both passive / active
transport; secreted from peritubular capillaries

Reabsorption – glucose, salts, AA, and water are reabsorbed from filtrate & return to blood; takes
place namely in PROXIMAL convoluted tubule (active)

Concentration – when dehydrated volume of fluid in bloodstream is low so you need to make
small amounts of concentrated urine => ADH prevents water loss by making distal tubule
permeable to water /// when Blood Pressure is low => aldosterone increases reabsorption of Na+ by
distal nephron which increases water retention (serum [Na+] increases BP)
** Selective permeability of the tubules establishes an osmolarity gradient in the surrounding interstitial fluid
*** Urine is hypertonic to the blood and contains a high urea and solute concentration.
Osmolarity Gradient – created by exiting / entering of solutes; increases from cortex to medulla
Counter Current Multiplier - descending loop permeable to water & ascending is permeable to salts / ions; this
makes the medulla very salty and facilitates water reabsorption
Excretion in Plants – excess CO2, waste O2, and H2O (g), leave by diffusion through stomata and lenticels
This process is called transpiration
Chapter 12.5 – Integumentary System
Functions of the Integumentary system
Guard the body’s physical and biochemical integrity
Maintain body temp
Sensory information
The three layers of skin
1.
Epidermis – superficial; epithelial tissue
a. Stratum corneum – 25-30 dead layers; filled w/ keratin and surrounded by lipids
i. Lamellar granulues make it water repellent
b. Stratum lucidum – only in palms and soles of feet, and finger tips; 3-5 layers, clear/dead
c. Stratum granulosum–3-5 layer of dying cells; lamellar bodies release hydrophobic lipids
d. Stratum spinosum – strength and flexibility; 8-10 layers held together by (desmosomes-keratin
involving adhesion proteins)
e. Stratum basale (germinativum) – stem cells dividing; attached by basement membrane
f.
2.
3.
Dermis – primarily connective tissue; collagen and elastic fibers; contains hair follicles, glands, nerves, and
blood vessels
a. Papillary region – top 20%
b. Reticular region – dense connective tissue, collagen and elastic fibers; packed with oil glands,
sweat gland ducts, fat, and hair follicles; provides strength, and elasticity (stretch marks are dermal
tears)
Hypodermis (subcutaneous) – not part of skin; areolar and adipose tissue; fat storage; pressure sensing
nerve endings; passage for blood vessels
Glands of the Skin
1. Sebaceous (oil) glands – connected to hair follicles; absent in palms and soles
2.
3.
4.
Sudiferous (sweat) glands
a. Eccrine (most of the body)- regulate temperature through perspiration; eliminate urea
b. Apocrine – armpits, pubic region, and nipples; secretions are more viscous
Creuminous (wax) glands – found in ear canal; barrier to entrance
Mammary (milk) glands
Chapter 13 – Animal Behavior
Kinds of Animal Behavior
1. Simple and Complex Reflexes
a. Simple- automatic response to stimulus controlled @ spinal cord (lower animals)
b. Complex- automatic response to significant stimulus (controlled @ brains stem or even cerebrum)
i. Ex: Startle response- controlled by the reticular activating system
2. Instinct- behavior that is innate, or inherited
a. Ex: In mammals, care for offspring by female parents
3.
Fixed action patterns (FAP)- innate behaviors following a regular, unvarying pattern. Initiated by a specific
stimulus (releaser), and completed even if original intent of behavior cannot be fulfilled
a. Ex: Goose methodically rolling egg back to nest even if it slips away or is removed
b. Ex: Male stickleback fish defending territory against any object with red underside
c. Ex: Swimming actions of fish/flying actions of locusts
4.
Imprinting- innate program for acquiring specific behavior only if appropriate stimulus is experienced
during critical period. Once acquired, trait is irreversible
a. Ex: Gay goslings accepting any moving object as mother during first day of life
5.
Associative learning- occurs when an animal recognizes (learns) that events are connected. A form called
classical conditioning occurs when animal performs behavior in response to substitute stimulus rather than
normal
i. Ex: Dogs salivate when presented with food. PAVLOV bell ringing prior to food, could
stimulate salivation with bell alone
b. Trial-and-error learning (OPERANT CONDITIONING)- another form of associative learning
that occurs when animal connects its own behavior with environmental response, reward. If
response is desirable (positive reinforcement), animal will repeat behavior. If undesirable (painful),
animal avoids behavior)
i. Learned behavior can be reversed in behavior no longer elicits the response (extinction)
c. Spatial learning- Another form of associative learning. Animal associates attributes of landmark
with reward of identifying and returning to that location
i. Ex: Wasps able to associate pinecones with location of nest (lost upon removal)
6.
Habituation- repeated stimulation results in decreased responsiveness
a. Sea anemones disregarding repeated “feeding” stimulation with a stick
7.
Observational learning- animal copies behavior of another without having experienced any feedback
themselves
a.
8.
Ex: All monkeys followed lead by washing off potato in water
Insight- When animal exposed to new situation, performs a behavior that generates (+) outcome
a. Chimpanzee stacks boxes to reach bananas previously out of reach
Animal Movement
1. Kinesis- Undirected change in speed of animal’s movement in response to stimulus. Slow down in favorable
environment and speed up in unfavorable
a. Ex: animals scurrying when rock is lifted up
2. Taxis- Directed movement in response to stimulus. Either toward or away from stimulus. Movement toward
light is called phototaxis
a. Ex: moths moving toward light, sharks moving toward food odors
3. Migration- Long-distance, seasonal movement of animals. Usually in response to availability of
food/degradation of environmental conditions
a. Ex: migration by whales, birds, elk, insects, and bats to warmer climates.
Communication in animals
1. Chemical- chemicals used for communication are pheromones. Chemicals that trigger changes are called
releaser pheromones; those that cause physiological changes are called primer pheromones
a. Ex: Doe in heat – releaser pheromones
b. Ex: Queen bees and aunts secrete primer pheromones to prevent development of reproductive
capability
2. Visual- during displays of aggression (agonistic behavior) or during courtship
a. Ex: aggression- wolves baring teeth/ submission- laying on back
b. Ex: Male sage grouse assemble into leks to perform courtship dance
3. Auditory
a. Ex: whale sound, elephant inphrasound, frog calls, and songs of male birds
4. Tactile
a. Common in social bonding, infant care, grooming, and mating
Foraging behaviors
1. Herds, flocks, and schools
a. Provide benefit of concealment, vigilance, and defense
2. Packs
a. Allow members to corner and attack large prey
3. Search images
a. Help animals find favored or plentiful food
i. Ex: Black and white search image = police car for humans
Social Behavior
1. Agonistic behavior - (aggression and submission)- Ex: dog wagging tail
a. Originates from competition from food, mates, or territory
b. Agnostic behavior is ritualized, so injuries and time spent in contests are minimized
2. Dominance hierarchies – indicate power and status relationship in a group
a. Pecking order- linear order of status used to describe dominance hierarchy in chickens
3. Territoriality- active possession and defense of territory- ensures adequate food/place to mate
4. Altruistic behavior- seemingly unselfish behavior- when an animal risks its safety in order to help another
individual rear its young
a. Actually increases inclusive fitness (fitness of individual plus relatives)
b. Kin selection- natural selection that increases inclusive fitness
c. Ex: haplodiploid reproductive system of bees- males are haploid and females and queen are diploid.
Inclusive fitness of female workers is greater if she promotes production of sisters
Chapter 14 – Ecology
Environment
Abiotic – nonliving (temp, climate, light and water availability, topology)
o Sunlight –

Photic zone in water = light penetrates; all aquatic photosynthesis

Aphotic zone – only animal and other heterotrophs
o Oxygen – air is ~ 80% nitrogen, 20% oxygen
Biotic – all living things that directly or indirectly influence the life of the organism
Levels of Biological Organization (from specific to general)
1. Organism – individual unit of biological system
2. Population – group of organisms of same species (able to reproduce) in a given location
3. Community – populations of diff. plants and animals species (Ex: lawn, pond, forest, sea)
a. Biotic community – only includes the populations
4. Ecosystem – includes community and the abiotic environment (Ex: lawn, pond, forest, sea)
5. Biosphere – all portions of planet that support life (Ex: atmosphere, lithosphere, hydrosphere)
Interactions within the Ecosystem
Niche – defines the functional role of an organism in its ecosystem; what it eats, where and how it obtains
food, what climatic factors are optimal, nature of its predators, etc... every species is unique
o ***No two species can every occupy the same niche***
Habitat – physical place where organism lives
Nutritional Interactions within the Ecosystem
Autotrophs – manufacture their own food; photosynthetic plants and chemosynthetic bacteria
Heterotrophs – depend on autotrophs or other heterotrophs to obtain food and energy
-
Herbivores (w/symbiotic bacteria), carnivores, and omnivores
Interspecific Interactions
1. Symbiosis – intimate, often permanent association b/w two organisms; may or may not be beneficial; some
may be obligatory (one or both organisms cannot survive w/o the other)
a. Commensalism – one benefits, the other is unaffected

Remora and shark – remora gets food shark discards

Barnacle and Whale – barnacle gets wider feeding opportunities
b. Mutualism – both organisms benefit

Tick bird and Rhinoceros – bird gets food (ticks) and rhino loses ticks

Lichen (fungus + algae) – algae produces food for itself and fungus; fungus provided
CO2 and nitrogenous wastes

Nitrogen Fixing Bacteria and Legumes – legumes provides nutrients for bacteria and
bacteria fixes nitrogen

Protozoa and Termites – protozoa digests cellulose for termites, termites protect and
provide food

Intestinal Bacteria and Humans – bacteria utilized food and provide vitamin K
c. Parasitism – benefits at the expense of the host; bacteria and fungi; live with minimum
expenditure of energy

Virus and Host cell – all viruses are parasites

Disease Bacteria and Animals – diphtheria is parasitic upon man; anthrax on sheep;
tuberculosis on cow or man

Disease Fungi and Animals – ringworm is parasitic on man

Worms and Animals – tapeworm and man (less dangerous = more survival)

Saprophytism – protists and fungi that decompose dead organic externally
2. Predation – carnivores and herbivores; evolve toward balance in which predator is regulatory infl.
3. Saprophytism – decompose dead organic matter externally and absorb nutrients (Ex: mold, slime molds,
mushrooms, and bacteria of decay)
4. Scavengers – consume dead animals (Ex: vulture, hyena, bacteria of decay)
*Intraspecific interactions between members of the same species are influenced by disruptive (competition) and
cohesive (reproduction and protection from predators and weather) forces*
Interactions between organisms and their Environment
1. Osmoregulation
a. Freshwater fish – live in hypoosmotic environment which causes excess intake of water; thus the
fish seldom drink and excrete dilute urine
b. Saltwater fish – live in hyperosmotic environment; constantly drinking and excreting salt across
their gills
c. Arthropods – secrete solid uric acid crystals to conserve water
d. Plants – possess waxy cuticles on leaf surface and stomata and have stomata on the lower leaf
surfaces only; leaves shed in winter; desert plants have extensive root systems, fleshy stems, spiny
leaves, extra thick cuticles, and few stomata
2. Thermoregulation
a. Cold-blooded (poikilothermic) –vast majority of plants and animals; body temp. is close to that of
surroundings, so metabolism is radically affected by environmental temp.
b. Warm-blooded (homeothermic) – make use of heat produced by respiration; physical adaptations
like fat, hair, and feathers retard heat loss (Ex: mammals and birds)
Energy flow within the Ecosystem
1. Food Chain
a. Producers – autotrophic green plants; always initial step in food chain
b. Primary Consumers – animals which consume green plants; herbivores
c. Secondary Consumers – consume primary consumers; carnivores
d. Tertiary Consumers – animals that feed on the secondary consumers
e. Decomposers – saprophytic organisms and organisms of decay
2. Food Web – the greater number of pathways in a community food web, the more stable the community is***
3. Food Pyramids – Second Law of Thermodynamics states that every energy transfer involves a loss of energy
a. Pyramids of energy – producer organism at base of pyramid contains greatest amount of energy;
smallest amount of available energy at the top of the pyramid
b. Pyramid of mass – each level can support a successively smaller biomass
c.
i. Ex: 300lb foliage  125 lb insects  50lb hens  25 lb of hawks
Pyramid of numbers – consumers higher in food chain are usually larger and heavier; lower
organisms have greater total mass, so there must be more of them
Nitrogen Cycle – decay, nitrifying, denitrifying, nitrogen-fixing (lighting and nitrogen-fixing bacteria)
4 Types of Bacteria involved in Nitrogen Cycle:
1. Decay – nitrogen in the form of NH3 is released from dead tissues
2. Nitrifying – convert NH3  NO2 (nitrite)  NO3- (nitrate)
3. Denitrifying – convert NH3 => N2 … back to nitrogen-fixing
4. Nitrogen-fixing – N2  NO3- … by bacteria on the roots of legumes
Carbon Cycle
1. Gaseous CO2  glucose (by plants through photosynthesis)
2. Glucose  CO2 (by animals that eat plants and use as fuel)
3. CO2 released to air and other organic carbon locked within organism until death; upon death, decay
process by bacteria returns CO2 to air
Climax Community – stable, living (biotic) part of ecosystem; populations & ecosystem exist in balance
Depends on all abiotic factors: rainfall, soil conditions, temp, shade, etc.
Persists until major climatic or geological change affects populations
Ecological Succession – orderly process by which one biotic community replaces another until a climax community is
established
A community stage is identified by a dominant species; Ex: grass in grassland community
Ecological succession in a Pond
1. Pond: Plants such as algae, pondweed. Animals such as protozoa, insects, fish
2. Shallow water-pond fills in: Reeds, cattails, water lilies
3. Moist land: grass, herbs, shrubs, willow trees. Frogs, snakes
4. Woodland: climax tree – perhaps pine or oak
World Biomes
Terrestrial Biomes
1. Desert – minimal concentrated rain, growing season = days after rain, small plants and animals
2. Grassland – low rainfall, no shelter for herbivores, animals have long legs/hooved
3. Tropical Rain Forest – high temps, torrential rains; vegetation does not shed leaves; epiphytes (plants
growing on other plants) and saprophytes (decomposers)
4. Temperate Deciduous Forest – cold winters, warm summers, moderate rainfall; trees shed leaves
5. Temperate Coniferous Forest – cold, dry (fir, pine, spruce); needles for H2O conservation
6. Taiga – less rainfall, long winters – inhabited by spruce; floors contain moss, lichen
7. Tundra – treeless, frozen; short summer, very short growing season when round becomes wet and marshy.
Lichens, moss, polar bears, oxen
8. Polar – frozen, no vegetation, terrestrial animals
Aquatic Biomes
1. Marine – contain relatively constant amount of nutrient materials and dissolved salts
2.
3.
Freshwater – hypotonic to organisms; affected by variations in climate and weather (temp. varies)
rain shadows – represent a reduction in rainfall on the leeward side of a high mountain
Chapter 15 – Classification – “Kings Play Chess On Finely Ground Sand”
FIVE KINGDOMS: (1)Monera (2)Protista (3) Fungi (4) Plantae (5) Animalia
Kingdom Monera (bacteria) – prokaryotes that reproduce Asexually; lack nucleus; circular DNA (transcription and
translation occur in same place at same time); cell wall made of peptidoglycan which contains D-alanine (animal AA
have L-configuration**) ; Gram-positive have thick peptidoglycan; Gram-negative have thin peptidoglycan but have
additional outer layer; three mechanisms for acquiring new genetic material : Transduction (fragments of bacterial
chromosome accidentally packaged into lysogenic phage). Transformation, Conjugation (once cell copies DNA =>
transferred through bridge/ F+ is male)
A. Cyanobacteria (blue-green algae)– *NOT same algae from protista)*; cell wall, have
photosynthetic pigments; NO flagella, NO true nucleus, NO true mito, NO true chloroplasts
B. Other Bacteria – single double-stranded loop of DNA (no nucleus); can be round (cocci), rods
(bacilli), or spiral (spirilla), almost all have cell walls
C. Archaea
Kingdom Protista – unicellular eukaryotes; membrane bound nucleus and organelles
A. Protozoa (“little animals”) –heterotrophic, rhizopods (amoebas) move w/ pseudopods; cilliophors
move w/ cilia; ex: Paramecium
B. Algae – photosynthetic; ex: phytoplankton and euglena (move w/ flagellum)
C. Slime molds – often placed in Fungi, but more directly related to protists
Kingdom Fungi – eukaryotes; multicellular; heterotrophs (differentiates them from plants); may be saprophytic or
parasitic; Ex: yeast, lichen, mushrooms; reproduce sexually (haploid adults) or asexually (spore formation, budding,
fragmentation)
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hyphae – branching filament of fungi, most are divided by septa (perforated w/ holes large enough
for organelles), collectively known as mycelium
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Classes: zygomycetes (ex. bread mold), basidiomycetes (ex. mushrooms), ascomycetes (ex. sac
fungi)
Kingdom Plantae – multicellular; non-motile, photosynthetic autotrophs; differentiation of tissues (photosynthetic,
supportive, vascular, absorptive (rhizoids=complex roots); alternation of generations (reproduction)
1.
Division Bryophyta – simple plants; must live in moist places; gametophyte is dominant; sporophyte
develops into archegonium; NO xylem (so lack support)
Mosses – primitive; gametophyte and sporophyte grow together
Liverworts – leaf-like plant; consists of lower part (rhizoids), middle part (food
storage), upper part (photosynthetic)
Division Tracheophyta (vascular plants) – radial symmetry; grow to great heights; sporophyte dominant;
contain xylem and phloem; anchored by roots instead of rhizoids; sporophyte dominant
i.
ii.
2.
Psilophytes (fern-like) – most primitive; rhizoids instead of roots, one vascular bundle
Lycophyta (club mosses) – roots, non-woody
Sphenophytes ( horsetail) – roots, hollow-jointed stems
Pterophyta (ferns) – evolved from psilopsids, many vascular bundles; sperm are
flagellated; grow from rhizome; sporangium is under leaves
Division Coniferophyta – gymnosperms (naked-seeded plants); megaspores (large female cones) and
microspores (small male cones); specialized cambium tissue allows for secondary growth; gymnospoerms
can grow in diameter as well as length; sporophyte is dominant
i.
ii.
iii.
iv.
3.
a.
4.
Cycads, pines, spruce, firs – (most are evergreens / non-deciduous)
Division Anthophyta – angiosperms; covered seeds; most abundant of all plants; flowers as their principle
reproductive structure.
a. Male: Anther of male stamen produces microspores
b. Female: Ovary of female pistil produces megaspores; stigma receives pollen
a.
b.
Monocotyledons (leaves w/ parallel veins)
i.
Scattered vascular bundles
ii.
Seeds with single cotyledons (seed leaves)
iii.
Most non-woody – lack cambium
iv.
Flower parts in multiples of 3
v.
Ex: grasses (wheat, corn, rye, rice), sugar cane, pineapple, irises, bananas, orchids,
palms (woody monocots)
Dicotyledons (net veined leaves)
i. Vascular bundles about rind within central cylinder
ii. Two seed leaves
iii. Can be woody
iv. Flower parts in multiples of 4 or 5
v. Ex: maple, apple, potatoes, carrots, goldenrods, buttercups
Kingdom Animalia – multicellular, motile, heterotrophic organisms w/ differentiated tissues; most have bilateral
symmetry; all employ some form of locomotion
1. Porifera (sponges) – two layers of cells; have pores; sessile (fixed)
2. Cnidarians (jellyfish, coral, hydra) – digestive sac sealed at one end; net nerves; two layers of cells
(ectoderm/ endoderm); RADIALLY symmetrical
cnidoblasts – specialized cells located in the tentacles and bodywalls of coloenterates; interior of
cnidoblasts filled with stinging cells (nematocysts)
Platyhelminthes (flat worms) – bilateral symmetry; 3 layers of cells (solid mesoderm); NO circulatory
system; nervous system consists of eyes, anterior brain ganglion & longitudinal nerve cords
Nematoda (round worms) – long digestive tubes & anus; solid mesoderm; NO circulartory system; nerve
cords and nerve ring
Annelida (earthworms) – possess coelom (true body cavity – in mesoderm); well defined systems including
nervous, circulatory, and excretory
Mollusca (clams and octopi) – softbodied & possess mantles which secrete calcareous (calcium carbonate);
breathe by gills; chambered hearts; blood sinuses; nerve chords
a. Class Gastropoda – largest Molluscan class; ex. slugs & snails; characterized by single shell
b. Class Cephalopoda – octopus and squid
Arthropoda (insects, spiders, crustaceans) – jointed appendages, chitinous exoskeleton, and open circulatory
systems (sinuses)
a. Insects – three pairs of legs, spiracles, tracheal tubes for breathing
b. Arachnids – four pair of legs and “book lungs”
c. Crustaceans – segmented body with variable number of appendages and have gills
a.
3.
4.
5.
6.
7.
8.
Echinoderms (starfish and sea urchin) – RADIALLY symmetrical; regeneration; evolutionary evidence
suggesting a link b/w echinoderms and chordates
9.
Chordates (most simple: lancelets  most complex: vertebrates) – notochord present at some stage in
development
a. Invertebrates
i.
Lancelets and tunicates (like amphioxus below); retains notochord, but no backbone
ii.
Vertebrates
i.
Fish – possess 2 chambered heart; gills; external fertilization
a) Jawless – sucking mouth; retain notochord; primitive (Agnatha)
a. Ex: lamprey and hagfish
b) Cartilaginous – jaws and teeth; reduced notochord; Ex: shark (chondrichthys)
c) Bony – most prevalent; lack notochord; ex trout (Osteichthys)
ii.
Amphibia – Larval stage (tadpole) has gills, tail, and no legs; Adult has lungs; 3
chambered heart; external fertilization; eggs are laid in water w/ jelly-like secretion
iii.
Reptiles – lungs; internal fertilization; leathery eggs; cold blooded; 3 chambered heart
iv.
Birds – warm blooded; 4 chambered heart
a) long Loop of Henle = concentrated urine = uric crystals
v.
Mammals – warm blooded; feed offspring w/ milk from mammary glands
a) Monotremes – leathery eggs, horny bills, milk glands but no nipples
a. Ex: duckbill platypus and spiny anteater
b) Marsupials – pouched animals. Embryo begins development in uterus and
completes while attached to nipples in pouch
a. Ex: kangaroo, opossum
c) Placental mammals- embryos develop fully in uterus; placenta attaches
embryo directly to uterine wall and provides for food, oxygen, and waste
exchange
a. Ex: bat, whale, mouse, and man
Viruses – non-living
- Reproduction
1. Lytic cycle – results in destruction of infected cell; viral DNA exists and replicated separate from
the host bacterial DNA
2. Lysogenic cycle – integration of the bacteriophage DNA into bacterial genome
b.
Chapter 16 – Evolution
Microevolution – how populations of organisms change from generation to generation and how new species originate
Macroevolution – describes patterns of changes in groups of related species over broad period of geologic time; the
patterns determine phylogeny(the evolutionary relationship among species and groups of species)
Evolutionary order: bryophytes  gymnosperms  angiosperms
Evidence for Evolution
1. Paleontology
a. Types of fossils:
1. Actual remains
2. Petrification – minerals replace the cells of an organism
3. Imprints – impressions left by an organism (Ex: footprints)
4. Molds – form in hollow spaces of rocks, as organism within decays
5. Casts – minerals deposited in molds
2.
3.
4.
5.
Significant Fossil remains found
1. Trilobite – primitive crustacean (relative of lobster); dominant during Paleozoic
2. Dinosaurs – dominant during Mesozoic era
3. Eohippus – primitive horse (four toes, short, pointed teeth); gradual change to modern horse (one
toe, flat teeth)
4. Woolly mammoth – hairy elephant
5. Saber-tooth tigers – preserved in asphalt tar pits
6. Insects – preserved in amber (fossilized resin oozed from trees)
7. Archaeopteryx – missing link between reptiles (has teeth and scales) and birds (has feathers)
Biogeography – unrelated species in different regions of the world look alike when found in similar
environments (North American rabbits (placental) and Australian wallaby (marsupial)
Embryology – similar stages In development (ontogeny) among related species
i. Ex: gill slits and tails found in fish, chicken, pig, and human embryos
Comparative anatomy
i. Homologous Structures – COMMON ANCESTOR; same basic anatomical feature; Ex wings of
bat, flipper of whale, forelegs of horses, arms of man
ii. Analogous Structures – DIFFERENT origins; have similar functions w/ different patterns of
development; (Ex: wings of fly and wings of bird)
Molecular Biology – closely related species share higher % of sequence than distantly related species (Ex:
more than 98% of nucleotide sequence in humans and chimpanzees is identical)
Natural selection – differences in survival and reproduction among individuals in population as a result of their
interaction with the environment
Darwin’s Theory for Evolution by Natural Selection
1. Populations possess enormous reproductive potential.
2. Population sizes remain stable.
3. Resources are limited.
4. Individuals compete for survival.
5. There is variation among individuals in a population.
6. Mach variation is heritable.
7. Only the most fit individuals survive.
8. Evolution occurs as favorable traits accumulate in the population.
Types of Selection
1. Stabilizing – eliminates individuals that have extreme or unusual traits
2. Directional – favors traits that are at one extreme of a range; opposite extreme selected against
a. Ex: Insecticide resistance – few individuals survive and proliferate
b. Ex: industrial melanism – selection of dark-colored varieties in various species
3. Disruptive (diversifying) – environment favors extreme or unusual traits, select against common
a. Ex: On lawns, short weeds predominate; in fields; tall weeds predominate
4. Sexual – differential mating of males (sometimes females) in a population; traits that allow males to increase
mating frequency have selective advantage, females can increase fitness by increasing quality of offspring by
choosing superior males
a. Sexual selection often leads to sexual dimorphism – a kind of disruptive selection
5. Artificial – carried out by humans when they sow seeds or breed animals that possess desirable traits
Sources of Variation
1. Mutations – “raw material” for new variation; can invent new alleles
2. Sexual Reproduction – creates individuals with new combination of alleles
a. Crossing over – occurs during prophase I
b. Independent assortment of alleles – during metaphase I
c. Random joining of gametes – during fertilization
3. Diploidy – presence of two copies of each chromosome in cell
a. Recessive alleles can be “hidden” from natural selection
4. Outbreeding – mating with unrelated partners
5. Balanced polymorphism – maintenance of difference phenotypes in a population
a. Heterozygote advantage – ex: sickle cell heterozygote = selective advantage in Africa
b. Hybrid vigor (heterosis) – superior quality of offspring set resulting from crosses between two
different inbred strains
i. Ex: Cross two inbred corn strains  hybrid more disease resistant, higher yield
c. Frequency-dependent selection (minority advantage) – least common phenotypes have a
selective advantage
i. Ex: Predator forming a search image of their prey; this results in phenotypes alternating
between low and high frequencies (maintains polymorphism)
Neutral variation – variation without selective value (Ex: fingerprints in humans)
Causes of Changes in Allele Frequencies
1. Natural selection – increase/decrease of allele frequency due to impact of environment
2. Mutations – introduce new alleles that rarely produce a selective advantage
3. Gene Flow – introduction/removal of alleles from population through emigration or immigration
4. Genetic Drift – random increase/decrease in alleles; effect can be strong in small populations; (Ex: flipping
coin 1000 times versus 5 times… probability of getting ½ much higher in former)
a. Founder effect – allele frequencies in group of migrating individuals are, by chance, not the same
as that of their population of origin (Ex: polydactylism in Amish community; after 200 years, trait
among 8000 person Amish community was higher than occurrence in remaining world population
b. Bottleneck – occurs when population undergoes a dramatic decrease in size; small population
becomes severely vulnerable to genetic drift
i. Ex – floods, volcano eruption, and ice ages
5. Nonrandom mating – individuals choose mates based upon their particular traits
a. Inbreeding – individuals mate w/ relatives
b. Sexual selection – females choose males based upon appearance, behavior, or ability to defeat
males in other contests
Genetic (Hardy Weinberg) Equilibrium – when allele frequencies in a population remain constant from generation to
generation – NO EVOLUTION – (p2+2pq+q2=1)
1. All traits are selectively neutral (no natural selection)
2. No mutations
3. Population isolated from other populations (no gene flow)
4. Population is large (no genetic drift)
5. No net migration
6. Mating is random
Speciation – the formation of new species
1.
2.
Allopatric speciation – population is divided by geographic barrier (no interbreeding btw pops.)
a. If gene pools sufficiently diverge, interbreeding will not occur now different species
Sympatric speciation – speciation without geographic barrier
a. Balanced polymorphism – subpopulations with similar characteristics as reproductively isolated
from other subpopulations
i. Polyploidy – possession of more than the normal 2 sets of chromosomes; often occurs in
plants; results in meiosis of a tetraploid individual continuing to produce diploid gametes
 reproductive isolation
ii. Hybridization – two distinctly different forms of a species mate and produce progeny
along a geographic boundary called a hybrid zone; genetic variation of hybrids is greater
than that of either parent, permits population of hybrids to evolve adaptations to
environmental conditions in hybrid zone
b. Adaptive radiation – relatively rapid evolution of many species from a single ancestor; occurs
when ancestral species is introduced to an area where diverse geographic or ecological conditions
are available for colonization
i.
Ex: marsupials of Australia began with colonization and adaptive radiation of a single
ancestral species
ii. Ex: 14 species of Darwin’s finches evolved from single ancestral South American
mainland species
Maintaining Reproductive Isolation
Prezygotic isolating mechanisms
1. Habitat isolation – species do not encounter each other
2. Temporal isolation – species mate or flower during different seasons/time of day
3. Behavioral isolation – species does not recognize another species as mating partner because it does not
perform the correct courtship rituals, display proper visual signals, sing correct songs, or release proper
chemicals
4. Mechanical isolation – male and female genitalia are structurally incompatible/flower structures select
for different pollinators
5. Gametic isolation – male gametes do not survive in environment of female gamete; or when female
gametes do not recognize male gametes
Postzygotic isolating mechanisms
1. Hybrid inviability – zygote fails to develop properly, dies before maturity
2. Hybrid sterility – hybrids become functional adults, but are sterile
3. Hybrid breakdown – hybrids produce offspring that have reduced viability
Patterns of Evolution
1. Divergent evolution – two or more species that originate from common ancestor
2. Convergent evolution – two unrelated species that share similar traits (due to similar ecological conditions
or lifestyles); they share analogous traits
a. Ex: eyes of squids and vertebrates functionally similar, but originate from different tissues during
embryological development  evolved independently
3. Parallel evolution – two related species that have made similar evolutionary changes after divergence from a
common ancestor
4. Coevolution – tit-for-tat evolution of one species in response to new adaptations that appear in another
species
a. Occurs between: predator and prey, pollinators and flowering plants, pathogens and immune
system
Macroevolution – patterns of evolution for groups of species over extended periods of time
1. Phyletic gradualism – evolution occurs by gradual accumulation of small changes
2. Punctuated equilibrium – evolutionary history consists of geologically long periods of stasis with little or
no evolution, interrupted by geologically short periods of rapid evolution; in this theory, absence of fossils
revealing intermediate stages of evolution is considered to confirm this theory
The Origin of Life (chemical evolution)
Heterotroph theory – first cells were heterotrophs; incapable of making their own food
1. The earth and its atmosphere formed – atmosphere consisted of CO, CO2, H2, N2, H2O, S, HCL, HCN,
but NO O2
2.
The primordial seas formed – earth cooled  gases condensed to produce primordial soup
3.
Complex molecules were synthesized – inorganic  organic, acetic acid, formaldehyde, amino acids
(These would serve as building blocks for polymers) – only possible because NO OXYGEN
4.
Polymers and self-replicating molecules synthesized – dehydration condensation; proteinoids are
abiotically produced polypeptides
5.
Organic molecules concentrated and isolated into protobionts (precursors of cells)
6.
Primitive heterotrophic prokaryotes formed – living organisms that obtain energy by consuming organic
substances (sourced from organic “soup”)
7.
Primitive autotrophic prokaryotes formed – heterotrophautotroph as a result of mutation
8.
Oxygen and ozone layer formed; abiotic chemical evolution ended – oxygen produced as a byproduct of
photosynthetic activity of autotrophs; interaction of UV light and O2 produced ozone layer
9.
Eukaryotes formed (endosymbiotic theory) – eukaryotic cells originated from a mutually beneficial
association among various prokaryotes; proposes that mitochondria and chloroplast were once prokaryotic
cells, living inside larger host cells.
a. Mitochondria and chloroplasts possess their own (circular) DNA
b. Ribosomes of mitoc. and chloroplasts resemble those of bacteria and cyano (size/seq.)
c. Mitoc. and chlor. reproduce independently of eukaryotic host cell by process similar to binary
fission
d. Mitoc. and chlor. have two membranes (the second of which could have been acquired during the
endocytosis of the original prokaryote)
e. Thylakoid membranes of chloroplasts resemble the photosynthetic memb. of cyano
adaptive radiation = divergent evolution
allopatric speciation – forming of a new species through the geographic isolation of groups from the parent population
(alla-geo)
Comparative Embryology – stages of development of embryo resemble stages in an organism’s evolutionary history;
human embryo passes through stages that demonstrate common ancestry – 2 layer gastrula of hydra (cnidaria) and 3
layer gastrula similar to flatworm
Vestigial Structures – structures that appear to be useless but had ancestral function; ex humans (appendix and tail),
horses (splints), python (legs reduced to bones)
Mullerian mimicry - two or more harmful species that are not closely related, and share one or more common
predators, have come to mimic each other's warning signals
Batesian mimicry – deceptive; harmless species has evolved to imitate the warning signals of a harmful species
directed at a common predator
Lamarckian Evolution – he was wrong; amount of change based on “use and disuse” of the organ; “inheritance of
acquired characteristics” (useful characteristic of one generation was transmitted to the next)
Darwin’s Theory of Natural Selection – pressures in the environment select for the organism most fit to survive and
reproduce

Chance variations occur b/c of mutation and recombination

If the variation is “selected for” by the environment, that individual will be more “fit” and more
likely to survive and reproduce

Survival of the Fittest leads to an increase of favorable genes in the gene pool
Gene Pool – all the alleles for any given trait in the population
Hardy Weinberg Principal – evolution can be viewed as changing gene frequencies within a population; when gene
frequency NOT changing => gene pool stable => NO evolution; this only happens under the FOLLOWING IDEAL
situation:
1. Population is very LARGE – (no change in allele frequency – random drift)
2. NO mutations that affect gene pool
3. Random mating
4. NO net migration in/ out of population
5. NO natural selection - Genes in population are all equally successful in reproducing
** Certain equilibrium exists so we can use Hardy-Weinberg equation:
p2 + 2pq + q2 = 1
p2 = frequency of TT // 2pq = frequency of Tt // q2 = frequency of tt
K-selected population – members have low reproductive rates and are roughly constant in size (ex. human population)
R – selected population – rapid growth, numerous offspring, fast maturation, little postnatal care (ex. bacteria)
Stanley L. Miller – demonstrated that the application of uv, heat, or a combination of these to a mix of methane,
hydrogen, ammonia, and water could result in complex organic compounds; primordial soup
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Misc.
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early atmosphere = CONHS (NH3, H2S, CH4)
stem cells produce lymphocytes by mitosis.
Glycine is the only optically inactive amino acid, since it has no chiral carbons.
pKa = half-equivalence pH. Amino acid deprotonates @ higher pH & becomes protonated @ lower pH.
gout – uric acid crystals deposit in tissues (ex. big toe)
Diabetes insipidus – caused by insufficient vasopressin production
PKU diseases – high amt. of the amino acid, phenylalanine, in blood; can cause mental retardation
Hashimoto’s disease – involves thyroid
Tay Sachs disease – lysosomal defect
In a warmer environment, the organism will want to increase its % of unsaturated fatty acids, so that fatty
acids will be more fluid and the melting point will decrease.
Prokaryotes lack cholesterol in their membranes, unlike eukaryotes.
hemizygous – only having one copy of a chromosome
Barr body – inactivated X chromosome
activity of sweat glands decrease as we age
as body temperature increases, blood vessels dilate
fertilization membrane – tough protective envelope developed by the sea urchin as a block to polyspermy
Arterioles offer the greatest resistance to blood flow in the circulation.
If the phenotype “skips” generations be suspicious of an autosomal recessive disorder. However if there is no
skip, it is most likely an autosomal dominant disorder. Be suspicious for X-linked recessive, if a father
doesn’t have the phenotype, none of his daughters display it.
Early earth consisted of a reducing atmosphere of CH4, NH3, H2, H2S, H2O.
t-RNA, m-RNA, r-RNA are produced in transcription. T-RNA will have “cloverleaf” structure
Cephalopods have high O2 demand, giant nerve fibers, & a closed circulatory system.
Sporazoans = division of Protozoan; diverse group of parasites (ex. plasmodium), cause malaria in humans
5 quarts of blood in an average sized adult.
In a typical antibody, the heavy and light chains are linked by disulfide bonds.
Erythroblastosis fetalis – Rh- mother (no Rh antigen, makes Rh antibodies), Rh+ fetus
Founder effects and bottlenecks occur when a population is originated or rebuilt from very few individuals =
ex. of genetic drift, amt. of genetic variation is very limited.
o Genetic/Population bottleneck – result of a disaster nearly wiping out a large population
Endocytosis uses ATP – AKA pinocytosis
plasmolysis – shrinkage of a cell due to water loss
Ontogeny recapitulates phylogeny – refers to embryonic stages of development of an organism repeat the
evolutionary history of the species
Streptococci – can be virulent, form chains; staphylococci form clusters
For each subsequent level in the energy pyramid, the energy increases by 10 1.
Purple/green bacteria, in the anaerobic sediments of lakes/ponds, carry out photosynthesis with H2, H2S, or
D as the electron donor, oxygen is not a byproduct.
pH of lysosome is 5, pH of cytosol is 7
Starch and glucose are polymers of alpha glucose. Polysaccharides are branched/linear. Peptides can only be
linear. Polysaccharides can have alpha or beta linkages.
Nerve gas – inhibitors of acetylcholinesterase, and cause death respiratory paralysis
Tay Sachs disease – autosomal recessive disease; lipid buildup in brain cells from lysosomal enzyme defect
Cells of PCT & DCT are very rich in mitochondria because of active transport. Ammonia = waste product of
aquatic animals; uric acid = birds, reptiles, & insects
Dynein = motor protein; used for movement in 9+2 flagella & cilia; may also be used in chromosomal
movement
Cytoskeleton = microtubules (ex. flagella & cilia), microfilaments, intermediate filaments.
Myoglobin curve = hyperbolic, Hemoglobin curve = sigmoidal. Myoglobin has higher affinity for O2 than
hemoglobin. Myoglobin has no change in O2 binding over a pH range.
Epidermis has no blood supply, and depends on dermis for oxygen and nutrients.
Higher metabolic rate = higher oxygen demand = hemoglobin not as saturated with O2
o Lower metabolic rate = lower O2demand = more saturated
A genetic map includes crossover frequencies.
homologues = homologous chromosomes and/or sister chromatids
ex. of autosomal recessive disorders = PKU disease, sickle-cell anemia, and galactosemia
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parasite & host population densities mimic each other
decrease in telomere = aging
recombinant DNA – modifying plasmid DNA for use as a vector to inject specific DNA into an cell
Episome – chromosome integrated with plasma DNA
apoptosis = planned cell death (ex. diabetes)
Necrosis = traumatic cell death
protobionts – metabolically active protein clusters; precursor to the prokaryote
People with Down Syndrome are prone to leukemia and Alzheimer’s disease.
ruminants – animals w/ stomachs of alkaline pH; usually 4 chambers capable of digesting cellulose
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Prostaglandins: Modified fatty acids which help induce fever, pain sensitization, and inflammation