Download Biology End of Course Test (EOCT) Study Guide

Document related concepts

Microbial cooperation wikipedia , lookup

Evolution wikipedia , lookup

Adaptation wikipedia , lookup

Symbiogenesis wikipedia , lookup

State switching wikipedia , lookup

Evolutionary history of life wikipedia , lookup

Introduction to evolution wikipedia , lookup

Transcript
Biology
End of Course Test (EOCT)
Study Guide
Venecia R Stewart, Ed.S.
Honors & General Biology Teacher
Campbell High School
Characteristics of Living Things
• Made of one or more cells
–Unicellular-made of one cell
–Multicellular-made of more than one
cell
Levels of Organization
Cellular Level
• Atom-basic unit of
matter
• Molecule
• Organelles
• cell (smallest unit of
living matter
• Tissue
• Organ
• Organ system
• Organism
Characteristics of Living Things
• Growth & Development
• Reproduction
• Asexual-organism reproduces
by itself
• Sexual-organism has to have
two different cells from
different organisms
• -------------------
Characteristics of Living Things
• Responds to Stimuli
• Requires Energy
Characteristics of Living Things
Metabolism- the sum total of
all of the chemical reactions
that take place in the body
Anabolism + Catabolism
= Metabolism
• Adaptation/Evolve
Two Parts of an Experiment
• Control Group
• Experimental
Group
–Standard for
comparison
–Receives the
variable
–Does not receive
the variable
–Only test for one
variable at a
–Receives the
time
placebo
Independent vs Dependent variable
• Independent variable—one factor should only
be tested at one time in an experiment
– (the one that “I” change); can be manipulated
• Dependent variable—the result from the
independent variable
• The outcome of the experiment
Scientific Method
• Hypothesis
– Educated guess
– Tentative explanation
about an event or
occurrence in nature
• Theory
– A hypothesis that has
been proven over and
over again
• STEPS
– State and Observe the
Problem
– Form a hypothesis
– Test the hypothesis or
Experiment
– Record & Analyze the
Data
– Form a conclusion
– Replicate Your Work
Levels of Organization
•
•
•
•
•
Ecological Level
Individual
Population
Community
Ecosystem
– Biotic factors
– Abiotic factors
• Biome
• Biosphere
Mutualism
• Mutualism—both
organisms benefit from
a relationship.
• Example—bird living on
top of a rhino. The bird
eats the insects off of
the rhino and the rhino
protects the bird.
Commensalism
Commensalism—
when one organism
benefits from a
relationship, and
the other is not
helped or harmed.
Example—bird
living in a tree.
Example-barnacles
on a whale.
Parasitism
• Parasitism—one
organism is helped
and the other is
harmed
• Example—a
tapeworm takes all
of the host’s food
• Exampleheartworms in a
dog’s heart
Food Chain
• Food Chain
–Simplest feeding
relationship
–Organisms are
arranged in a
linear sequence
Food Web
• A food web is a complex series of food chains.
Ecological Terms
• Detritus-is non-living
particulate organic material. It
typically includes the bodies or
fragments of dead organisms
as well as fecal material.
• Saprophytes-An organism,
especially a fungus or
bacterium, that grows on and
derives its nourishment from
dead or decaying organic
matter.
• Decomposers-break down
decaying or dead organisms
and return their nutrients back
into the soil; also known as
saprotrophs
• Detritivore-An organism that
feeds on and breaks down
dead plant or animal matter,
returning essential nutrients
to the ecosystem. Detritivores
include microorganisms
• Scavenger-feeds on dead and
decaying organic matter
present in its habitat
Chlorofluorocarbons (CFCs)
• Chlorofluorocarbon
(CFC) is an organic
compound that
contains carbon,
chlorine, and fluorine,
produced as a volatile
derivative of methane
and ethane
• Destroys the ozone
layer
Biomagnification
• “Biomagnification is • Bioaccumulation –
“General term describing
the process whereby
a process by which
the tissue
chemicals are taken up by
concentrations of a
an organism either
directly from exposure to
contaminant
a contaminated medium
increase as it passes
or by consumption of
up the food chain
food containing the
through two or more
chemical.” – U.S.
Environmental Protection
trophic levels.” Agency, 2010
Nowell and others,
1999
Biomagnification
DDTs were Banned Because of Their
Toxicity
• Biological Magnification
• Was a banned pesticide
that killed aquatic
plants and animals and
other wildlife
Acid Rain
(is created when sulfur dioxide and nitrogen oxides
combine with rainwater)
Trophic Levels
The bottom of the energy pyramid is
the plants/producers which are
autotrophs. As you move up the
food chain, you have consumers
(primary eats the plants and are
herbivores, secondary eats plants
and animals and are omnivores, and
the tertiary consumers are usually
carnivores and are known as top
predators.)
Trophic Levels
Energy Pyramid
• 90% of energy is lost to
heat and only 10% of
the energy moves up
the pyramid. That
means that the top
predator gets very little
energy, but primary
consumers that eat the
plants get a lot more
energy.
Pyramids of Numbers & Biomass
Describe the water, carbon,
phosphorus and nitrogen cycles.
• All matter in the universe is neither destroyed
nor created. Nutrients on earth are recycled
as well.
• Also known as Biogeochemical Cycles
Water Cycle
Carbon Cycle
Nitrogen Cycle
Phosphorus Cycle
Greenhouse Effect
Primary Succession.
• Primary succession is
when there is just rock,
and no soil for the
plants to grow on
• It is a very slow process
• Lichens and moss
(pioneer species) are
examples of the first
organisms to grow.
Secondary Succession
• Secondary succession is
when there is soil left
by a natural disaster.
For instance, a tornado
or flood does not wash
away all soil, giving
succession a base for
growing plants.
Aquatic & Terrestrial Biomes
• Marine—salt water biome that covers most of the earth.
• Freshwater—lakes, rivers, and streams
• Tundra—cold, no trees, has a layer of permafrost. Canada, Alaska, Northern
Russia;
• Taiga—cold, northern forest that has conifers. Also called boreal forest.
Canada, Alaska, etc. Animals include reindeer, moose, etc.
• Desert—hot during the day, and cold at night. Very little to no rain.
Northern Africa, South Western United States
• Grassland—Midwest United States. Good for farming, very little trees,
herbivore and grazing animals are abundant. Moderate rainfall and
moderate to cold temperatures.
• Temperate forest—Georgia is an example of temperate forest in the North
Georgia Mountains. Deer, fox, raccoons, bobcats. Moderate to cold
temperatures and moderate rainfall.
• Tropical rain forest—very rainy. Biomass is in the trees. Poor soil.
Abundance of animals and the most diverse species. South America is an
example; usually has a temperature of 25 C.
Carrying Capacity
• The carrying capacity is
the maximum number
of organism that an
environment’s
resources can sustain.
• If the population
exceeds the carrying
capacity, then
individuals will die
because of lack of
resources.
Population Growth Curves
Dispersion Patterns
Uniform is an even pattern of
Dispersion that results in
interactions among
individuals of a population.
Creosote bush and black
Bears are examples
Clumped is when individuals
are aggregated into patches,
is the most common in nature.
Elephants and the American
Bison are clumped in groups or
herds.
Random occurs when
individuals are spaced,
in a patternless, unpredictable way. Dandelions
and white-tailed deer
are examples.
Biodiversity
• Indigenous species
– A species that naturally
occurs in a particular
environment or
ecosystem
• Introduced species
– A species that humans
have placed into an
ecosystem or community
(either accidentally or
intentionally) in which it
does not naturally occur.
Density-Independent and Density Dependent
Factors
• Density independent factors are abiotic
factors that occur regardless of the size of the
population. Examples are hurricanes, floods,
and other weather factors.
• Density dependent factors are biotic factors
that depends on the size of the population.
Competition, disease, and predation are
examples of these factors.
Biotic vs Abiotic Factors
Competition
How does competition effect a
population?
Competition can affect population
size. The larger the population,
the greater the competition will
occur. Organisms will compete for
space, food, and mates.
What is demography? How does birth rate, death rate,
immigration, and emigration effect demography?
•
•
•
•
•
Demography is the study of the human
population
Birth rate—increases population
Death rate—decreases population
Immigration—organisms coming INTO a
population will increase the population size
Emigration—organisms EXITING a population
will decrease the population size
Describe the structure of an atom.
• Protons (positive charge)
• Neutrons (no charge)
make up the dense
nucleus of the atom.
Neutrons and protons
have an atomic size of 1
• Electrons (negative
charge) orbit in the shells
around the nucleus.
Electrons are very small in
comparison to protons
and neutrons and have a
mass of 0.
Macromolecules/Organic Compounds
• Name
Subunit
Function
Examples
• Lipids
Triglycerides
Long term storage of energy
Make up membranes
Fats, waxes, oils
• Carbohydrates Monosaccharide
• Proteins
Amino Acids
• Nucleic Acids Nucleotides
Short term energy
Main source of energy
Muscle building
Storage, transport
Hormones, enzymes
Sugars
Starches
Hemoglobin
Stores/transmits genetic information DNA, RNA
Enzymes? How do they work?
• Enzymes are proteins. They
are biological catalysts.
• An enzyme will bind to a
substrate to speed up
reactions.
• The enzymes will not be
used up in the reaction.
• It just lowers the activation
energy needed to start a
reaction.
• HINT! Remember:
reactants  products
Describe the properties of water and
how they support life on Earth.
•
Water is the most abundant
compound on Earth's surface,
constituting about 75% of the
planet's surface. In nature it exists in
liquid, solid, and gaseous states.
Many substances dissolve in water
and it is commonly referred to as the
universal solvent.
•
Water is a polar molecule
because the oxygen side is slightly
negative and the hydrogen side is
slightly positive. The three atoms are
constantly at a “tug of war” for their
electrons. This polarity helps water
to bind to other substances.
Types of Bonds
• Covalent Bonds-share
their electrons, are
strong bonds
• Hydrogen bonds-are
weak bonds; hold
nitrogenous bases
together
• Ionic bonds-transfer
electrons
• Peptide bonds-join
amino acids together
Prokaryotes and Eukaryotes
• Prokaryotes are simple cells with no nucleus. An example would
be bacteria.
• Eukaryotes have a nucleus and membrane-bound organelles. An
example would be plant and animal cells.
SCIENTISTS OF THE CELL THEORY
Scientists Who Contributed to the Cell Theory
The Cell Theory
Functions of the following organelles:
•
•
•
•
•
•
•
•
•
•
•
•
•
Nucleus—the center of the cell that controls all activities. “The Brain”
Ribosome—site of protein synthesis. On the Rough ER
Smooth ER-synthesizes lipids
Mitochondria—converts sugar into ATP for use in the cell. “Powerhouse” of the cell
Chloroplast—converts sunlight into glucose (sugar) for energy “Chlorophyll FILLS the chloroplast”
Only in plant cells. Where photosynthesis takes place in the leaves.
Cell (Plasma) Membrane—a semi-permeable structure that regulates what comes in and out of
the cell, “Gatekeeper of the Cell”
Golgi Apparatus-packages, modifies, secretes, and ships proteins to other parts of the cell
Cell Wall—Only in plant cells. This is a rigid structure that is outside the cell membrane. It
provides structure/shape and protection.
Lysosome—Uses enzymes to clean the cell of worn out parts or waste. “Cleans like Lysol!”
Vacuole—Mainly in plant cells. Stores water, minerals, and food. Usually the largest structure in
the plant cell. If the vacuole is filled, then the plant appears normal. If the vacuole is empty, the
plant leave appear to be wilted.
Cilia—hairlike structures on the outside of the cell that help the cell move and capture food
Flagella—one long hairlike structure that helps the cell move. Example is sperm cells.
Cytoplasm—a jelly like substance within a cell that fills the space. All reactions in the cell occur
here.
Plasma/Cell Membrane
Explain the difference between hypotonic,
hypertonic, and isotonic solutions and
how this effects movement across cell
membranes.
• Hypotonic solutions—There is more water (solvent) on
the outside of the cell then on the inside. The result is
water rushes into the cell making it swell and possibly
burst. “You swell up like a hippo in a hypotonic
solution.
• Hypertonic solutions—There is more water on the
inside of the cell than on the outside. The result is
that all of the water rushes out making the cell shrink.
• Isotonic solution—concentrations in the cell and
outside the cell are equally. There is no
NET
movement of concentration.
Osmotic Solutions
Passive Transport
• Passive transport—transport across a cell
membrane that requires no energy. The molecules
move down its concentration gradient from high to
low! (like rolling down a hill!)
Examples of passive transport—
Osmosis—diffusion of WATER across a
selectively permeable membrane
Diffusion—passive transport mainly of gases
Facilitated diffusion-passive transport of
substances using a carrier protein
Osmosis vs Diffusion
Facilitated Diffusion
Active Transport
• Active transport—transport
across a cell membrane AGAINST
a substances concentration
gradient. (like pushing a boulder
uphill!!)
Examples of active transport—
Endocytosis—bringing a
substance INTO a cell
“ENTERING=ENDO”
Phagocytosis—cell eating
Pinocytosis—cell drinking
Exocytosis—bringing a substance
OUT of a cell “EXITING=EXO”
Compare and contrast photosynthesis and
cellular respiration. What are the
chemical equations for each?
• Photosynthesis occurs in plant leaves in the
chloroplasts. It is a process in which sunlight
is converted to sugar
6CO2 + 6H2O + sunlight C6H12O6 (sugar) + 6O2
• Cellular Respiration occurs in the
mitochondria of a cell. It converts glucose to
make ATP
C6H12O6 + 6O2  6CO2 + 6H2O + 36 ATP
Photosynthesis
Steps of the Light Reaction of Photosynthesis
1. Light Absorption
2. Electron Transport Chain
3. Oxygen Production
4. ATP & NADPH Formation
Photosynthesis
Steps of the Dark
Reaction or Calvin Cycle
1. Carbon Fixation
RuBP + CO₂ -- PGA
1. Energy Consumption &
Redox Reactions
PGA --- PGAL
1. PGAL leaves the Cycle
2. Regeneration of RuBP
PGAL --- RuBP
Cycles 6 Times to make 1 Glucose Molecule
Fermentation
(Is an anaerobic process that produces lactic acid and alcohol)
Cellular Respiration
In prokaryotes
Cycles Twice
36 ATP in Eukaryotes (KNOW THIS)!
Stages of Mitosis
• Prophase—nuclear envelope & nucleolus break
down and chromosomes appear (Prepare)
• Metaphase—chromosomes line up in the center
of the cell (Middle)
• Anaphase—sister chromosomes are pulled apart
by spindle fibers (Apart)
• Telophase-chromosomes have reached opposite
poles, nuclear envelope, nucleolus and nuclear
membrane reappear (Two)
• Cytokinesis—two INDENTICAL daughter cells are
made by the division of the cytoplasm
The Cell Cycle & Mitosis
Meiosis
• Meiosis goes through two
phases of PMAT to
produce FOUR
GENETICALLY DIFFERENT
CELLS. The purpose of
meiosis is to produce sex
cells, or gametes—sperm
and eggs.
• Female gametes, or
_OVUM___, fuse with
male gametes, or
_SPERM__, to create a
_ZYGOTE__.
Crossing Over
Somatic Cell vs Gametes
• Somatic cell is the same
as a body cell; ex nerve
cell, skin cell
• Has a diploid
chromosome number
• Gametes are sex cells;
ex sperm and egg cells
• Have a haploid
chromosome number
Scientists of Heredity
• Watson & Crick
• Martha Chase & Alfred
Hershey
Gregor Mendel
• Rosalind Franklin
Genetics
Who was Gregor Mendel? What were his
three laws of heredity?
• Gregor Mendel was the “Father of Genetics”. He
studied pea plants to formulate his laws of heredity.
• The law of dominance—the dominant trait will always
show up in offspring
• The law of segregation—there are two alleles for each
trait, but they will separate individually into the
offspring.
• The law of independent assortment—traits are
expressed separately (example—just because of you
have brown hair does not mean you have brown eyes!)
Distinguish between dominant and
recessive; heterozygous and homozygous;
genotype and phenotype.
• Dominant traits are usually expressed and cover up the
recessive allele.
• Recessive traits are usually not expressed and can be covered
up by the dominant trait. Only two recessive alleles will show
up.
• Heterozygous alleles consist of two different alleles (one
dominant and one recessive Rr)
• Homozygous alleles are two same alleles (rr or RR)
• Genotype is the actually gene code (GG, Gg, gg)
• Phenotype is the physical expression of the trait (brown hair,
long necks, etc)
Sexual vs Asexual Reproduction
• Asexual reproduction produces the same
organism.
• Sexual reproduction gives a combination of two
different genes, with each parent donating half
their chromosomes to its offspring. This gives the
offspring an advantage of not having disorders
and other genetic abnormalities. They have the
possibility of getting the strongest traits from
both parents.
DNA Molecule
• It is a double helix
structure made up a
sugar, a phosphate and
nitrogen bases.
• The bases are ATGC.
Adenine, Guanine,
Cytosine, and Thymine.
A pairs with T, C pairs
with G
RNA Molecule
• A single stranded
molecule that carrying
genetic information. It
codes for proteins.
• The bases are AUGC.
Adenine, Guanine,
Cytosine and Uracil. A
pairs with U and C pairs
with G
DNA replication
Why is DNA replication necessary? When does
it occur?
• DNA replication occurs in
the S phase of interphase.
It is a semi-conservative
process in which the
newly formed dna strands
has one strand of the
original double helix
• One strand of DNA is
saved and one strand of
DNA is used to make a
copy
How does DNA code for a Protein?
(Transcription and Translation)
• DNA copies itself.
• mRNA reads the copied
DNA by transcription.
• mRNA leaves the nucleus
and travels to the
cytoplasm and attaches
to a ribosome
• tRNA codes this piece of
genetic material by
translation.
• This final code is read to
make an amino acid.
Genetic Crosses
• Test Cross
• When conducting a test
cross, use the recessive
genotype for the other
parent
• Monohybrid Cross
Dihybrid Cross
What are the major types of mutations?
How do mutations affect protein synthesis?
List some common mutagens.
•
•
•
•
Deletion where a base is left out.
Insertion in which a base is put into the code.
Substitution in which two bases are swapped.
In all of this, the bases will be read in a
different order and a mutation will occur. A
mutation is a permanent change in DNA.
• Common mutagens can be UV light,
pollutants, chemicals (drugs, alcohol, etc.)
Dominant & Recessive Disorders
• Dominant Disorders
• Achondroplasiadwarfism; is lethal in
the homozygous state
• Recessive Disorders
Nondisjunction Disorders
(failure of the chromosomes to properly separate)
Klinefelter’s Syndrome-males with
small testes, no pubic or facial hair,
long arms, large hands and feet,
slow learner -------------------
Distinguish between incomplete
dominance and codominance. Describe
sex-linked inheritance.
• Incomplete dominance—where two traits blend to
form an “in-between” trait. Example: a red flower and
a white flower could blend to form a pink flower.
• Codominance—where two alleles are equally
dominant. Therefore the result is both alleles showing
up. Example: a black cat and a white cat have black
and white striped kittens. Spots or stripes!
• Sex-Linked Traits—a trait (usually disorder) that only
occurs on the X chromosome. Therefore a female can
be a carrier (XhX) because the second allele will mask
the trait. A male cannot be a carrier and will always
show the trait XhY. The Y does not cover it up.
Co-dominance
Incomplete Dominance
Sex-linked Traits/Multiple Alleles
Blood Types are controlled by Multiple
Alleles. AB blood type is Co-dominant.
Pedigree Chart
Segregation of Alleles
(the separation of alleles)
Genetic Engineering
Cloning is the creation of an organism
that is an exact genetic copy of another.
Polymerase Chain Reaction (PCR)
• Polymerase chain reaction
(PCR), is a common method
of creating copies of specific
fragments of DNA. PCR
rapidly amplifies a single
DNA molecule into many
billions of molecules.
• In one application of the
technology, small samples
of DNA, such as those found
in a strand of hair at a crime
scene, can produce
sufficient copies to carry out
forensic tests.
Gel Electrophoresis
Gel electrophoresis is a way to measure
the lengths of DNA segments. It also
separates and analyzes macromolecules
(DNA, RNA and proteins) and their
fragments, based on their size and
charge
Restriction Enzymes
Human Genome Project
Transgenic Animals
•
•
•
Definition: An organism (typically a mouse) that is
engineered to carry a foreign gene, or transgene of
choice as part of its own genetic material.
Purpose: These animals are very useful for
delineating the function of newly discovered genes
as well as for producing useful proteins in large
animals.
Method: The gene to be introduced is first isolated
and engineered (using the techniques of genetic
engineering) to carry appropriate elements. The
transgene of choice is then injected into a fertilized
egg, which is obtained as follows:
- a female mouse is injected with several
hormones to cause it to produce numerous eggs
- the female is then mated with a male so that
some of the eggs are fertilized
- the eggs are collected before they divide and
are injected with the foreign genetic material
- these eggs are then transplanted back into
another female (the recipient female), in which
they can develop to term
Conclusion: In some of the eggs, the genetic
material integrates at a random site on a
chromosome and so becomes part of the mouse
cell's genetic material the animal resulting from
that egg will therefore carry that gene and so is
referred to as a "transgenic animal".
Transgenic Plants
• What is a Transgenic Crop?
• A transgenic crop is a
genetically modified organism
(GMO). Transgenic indicates
that a transfer of genes has
occurred using recombinant
DNA technology [1]. Generally
a transgenic crop contains one
or more genes that have been
inserted artificially either from
an unrelated plant or from
different species altogether.
• One of the reasons to modify
crops is to increase the
resistance of plants to insects
and diseases they may carry
Stem Cell Research
• Stem cells are
undifferentiated
cells that have the
potential to
become
specialized cells
for specific use.
Stem Cell Research
Ways to Test for Abnormalities of a
Fetus During Pregnancy
Chorionic Villus Sampling
Chorionic villi are microscopic projections
that line the chorion, the outermost layer
of the embryonic sac. Surgeons sample
these projections for genetic testing
because they contain the same genetic
material as a fetus.
• Amniocentesis
Amniocentesis is a
diagnostic procedure in which
a small amount of amniotic
fluid is withdrawn from the
amniotic sac, the membrane
that surrounds the fetus in the
uterus.
Charles Darwin
• Father of Evolution
• Traveled from 18311836
• Ship was the “HMS
Beagle”
• Famous book was “On
the Origin of Species”
Darwin’s Voyage
HMS Beagle
Geologic Time Scale
Geologic Time Scale
Geologic Time Eras
• There were four
geologic time eras
• Precambrian is the
earliest
• Paleozoic-animals
appeared
• Mesozoic-dinosaurs
became extinct
• Cenozoic-humans
appeared
Name and describe the 6 different types of
fossils?
• Casts—external view
• Mold—external view
• Trace fossils—footprints or other animal tracks that
animals leave behind
• Imprints—an outline of an organism (usually a plant)
that is left in the sediment and hardened
• Petrified fossils—best known, like dinosaur bone
deposits. The bones are replaced by minerals and are
hardened, but leaving scientists a great view of the
bone structure.
• Amber preserved and frozen fossils—whole
specimens and soft tissue is preserved.
Radioactive Dating/Half-life
• Radioactive Dating is the
process of determining the
age of an object by
measuring the amount of a
radioactive substance it
contains
• Half-life is the length of
time it takes ½ of a
substance to decay
Spontaneous Generation
(was disproven twice)
• Spontaneous generation is the idea that living
things came from nonliving things.
• Francisco Redi put rotting meat into a closed
flask and maggots did not appear.
• Louis Pasteur created a similar experiment
that show that no living organisms would
grow in a closed environment.
Endosymbiotic Theory
• The endosymbiotic
theory is based on
eukaryotes from
evolving prokaryotes.
• The nucleus,
mitochondria and
chloroplasts are
proposed to have
evolved during this
process.
Lamarck & Darwin
• Lamarck believed in “use and disuse”. He
believed that if you didn’t use a feature, it
would diminish in size or you would lose it
• Darwin created his theories of natural
selection which stated that the best traits or
adaptations would be passed on to offspring
• Survival of the fittest stated that only the
healthiest, best adapted organisms would
survive and reproduce
Natural Selection vs Artificial
Selection
• Natural selection is
when organisms adapt
to their environment
• Artificial selection is
when organisms are
bred for specific traits
Mimicry vs Camouflage
Uniformitarianism
• James Hutton
• Father of Geology
• Suggested that the earth
was much older and that
processes occurring in the
present were the same
processes that had
operated in the past, and
would be the processes
that operate in the future.
• Sir Charles Lyell whose
Principles of Geology
(1830) popularized the
concept of
uniformitarianism
Catastrophism
• Catastrophism-stated
that only violent
disasters could modify
the surface of the earth
• Is not the current
theory of Earth’s history
• Uniformitarianism is
the accepted theory
Three Types of Natural Selection
• Stabilizing Selection-- The extremes are selected against.
Example: height; mostly beings tend to the average
height- not too many really short ones or really tall
ones.
• Directional selection-- One extreme value is selected for.
Example: speed; faster is always better so a population
will tend to get faster over time.
• Disruptive selection-- The extremes are both selected for.
This type of selection is not as common as the first
two. Example: Prey-type animal with distinctive
markings which the predators know will over time
move away from the norm in both directions.
Modes of Natural Selection
Gradualism vs Punctuated Equilibrium
Hardy Weinberg Principle
•
•
•
•
Hardy–Weinberg Equilibrium
If Hardy–Weinberg Equilibrium is achieved
then no evolution occurs.
To achieve the equilibrium five conditions
must be met:
– Population must be very large.
– Population must be isolated from
other populations (no immigration or
emigration).
– No mutations
– Random mating
– No natural selection (i.e. every
individual has an equal chance of
survival)
If the five conditions are not met then
evolution occurs:
– There is a change in allele frequency
in the population.
– Hardy–Weinberg Equilibrium is not
present.
•
•
•
•
•
•
•
Consequences of Violations of the Five Conditions
A small population causes genetic drift
–
Changes in allele frequency due to chance
–
Example: a small number of coin tosses versus large number of
coin tosses
–
Special cases of genetic drift:
•
Bottleneck Effect
– Occurs when some event reduces the
population to a really small size.
– Example: Northern Elephant Seal population
was almost hunted to extinction—only about a
dozen individuals survived to repopulate the
current large population.
•
Founder Effect
– Occurs when a few individuals colonize a new
area.
– Example #1: immigration of religious groups (in
small numbers) to the United States that will
not reproduce with other individuals. They
maintain a very small isolated population.
– Example #2: Darwin's finches
Non-isolated population causes gene flow
–
Movement of individuals from one population to another,
resulting in interbreeding of what were once isolated populations.
–
Reduces genetic differences between populations.
Mutations cause new alleles to be introduced into the population.
Nonrandom mating causes more expression of recessive phenotypes
–
Inbreeding: mating between closely related partners
–
Assortative mating: individuals choose partners like themselves.
–
In both cases, two organisms carrying a recessive gene are more
likely to pair up, so a recessive phenotype (e.g. resulting from
genotype aa) is more likely to be expressed.
Natural selection causes the expression of successful alleles
–
Certain alleles provide traits that create a better ability to survive
and reproduce than the traits of other alleles do.
Bottleneck Effect
Founder Effect
Peppered Moth Phenomenon
• The peppered moth
phenomenon occurred
as a result of the
industrial revolution
• This is an example of
natural selection.
A cladogram is a phylogenetic tree.
Phylogeny-is the study of evolutionary biology which
depicts the evolutionary relationships among
organisms
Dichotomous Key
Homologous Structures
Analogous
Structures
• Analogous structures
are derived from
organisms living in
similar environments
but they are unrelated
to each other
Patterns of Evolution
• Divergent evolution is the
process of two or more related
species becoming more and
more dissimilar.
• The red fox and the kit fox
provide an example of two
species that have undergone
divergent evolution. The red
fox lives in mixed farmlands
and forests, where its red
color helps it blend in with
surrounding trees. The kit fox
lives on the plains and in the
deserts, where its sandy color
helps conceal it from prey and
predators.
Divergent Evolution/Adaptive Radiation
•
•
•
•
•
Related species
Different environment
Different adaptations
Develop new species
Diverge-move apart
Convergent Evolution
• Convergent
evolution means
unrelated species
become more and
more similar in
appearance as
they adapt to the
same kind of
environment
Convergent Evolution
•
•
•
•
Unrelated species
Similar environments
Similar adaptations (more alike)
Converge or come together
Taxonomy
• Domain, kingdom,
phylum, class, order,
family, genus, species
• Do Kings Play Cards On
Fine Glass Stools?
• Did King Philip Come Over
For Gumbo Soup?
What are the six kingdoms of biology
and what are the characteristics of
each?
• Archaeabacteria—bacteria that lives in extreme environments (heat,
chemicals) also a member of the kingdom Monera or Bacteria. Unicellular
and prokaryotic
• Eubacteria—bacteria that is common and lives on or in most organisms,
also a member of the kingdom Monera. Unicellular and prokaryotic
• Protista—A mixed category of most one cell organisms. Some are animallike, plant-like (because they perform photosynthesis), or fungus-like
(decomposers). Eukaryotic
• Fungi—decomposers that are multicellular organisms. These organisms
break down decaying material and help recycle it in the environment.
Eukaryotic
• Plantae—multicellular organisms that are autotrophs and perform
photosynthesis. They can reproduce by asexual or sexual reproduction.
Eukaryotic
• Animalia—multicellular and complex organisms that mostly reproduce by
sexual reproduction and most are heterotrophs. Eukaryotic
Classification of Organisms
Viruses vs Bacteria
• Bacteria are living organisms
and a virus is not living.
• Bacteria can become resistant
to antibiotics if they are used
repetitively
• A virus is not living because it
cannot survive independent of
a host organism.
• Viruses can reproduce but only
inside a host organism.
• Vaccinations are administered
as form of prevention from
viral diseases
Viruses have two cycles. The lysogenic cycles occur
when the virus is a part of the host’s body, but is not
actively reproducing. The lytic cycle is when the virus is
active and reproducing and effecting the host.
Describe the common structure of
fungi and its modes of reproduction.
• Most have exoskeletons
that make them very
structured. They can
reproduce by sexual
reproduction or asexual
reproduction by binary
fission. This occurs
when the organism
splits in half to make
two new organisms.
Vascular vs Nonvascular plants
•
•
Vascular plants have a root and “vein” system that can carry water and
minerals throughout the plants. These include trees and all plants that aren’t
mosses.
Nonvascular plants do not have a water transport system and are very low to
the ground. These include moss.
Alternation of Generations
Monocot vs Dicot
•
•
•
•
MONOCOTS
Leaf has parallel veins
Embryo with single seed pack
Flower parts in multiples of
three
• Stem vascular bundles
scattered
•
•
•
•
DICOTS
Embryo with two seed packs
Leaf is net-veined
Flower parts in multiples of
four or five
• Stem vascular bundles in a ring
How do plants reproduce?
• Asexually by splitting off or
having runners. (Grafting or
budding)
• Sexually by producing ovum
(seeds) and sperm in the
form of pollen. (Cross
pollination)
• Animals help spread the
seeds and pollen in their
feces or fur. (Vector
pollination)
• Wind and water can also
help plants spread their
seeds.
• The pollen falls on the
stigma of the same plant.
(Self-pollination)
Angiosperms vs Gymnosperms
Tropism is any type of cause-effect plant
movement.
• Phototropism- is plant
movement toward a
light.
• Thigmotropism is a
movement in which an
organism moves or
grows in response to
touch or contact
stimuli. The prefix
thigmo- comes from the
Greek for touch.
Geotropism
• Geotropism-the growth
of a living organism in
response to gravity, as
the downward growth
of plant roots.
Hydrotropism
• Hydrotropism is the
growth response of a
plant to water. Roots
exhibit positive
hydrotropism.
Chemotropism
• Chemotropism is the
growth response of a
plant to a particular
chemical. Roots grow
toward useful minerals
in the soil but away
from acids.
Thigmotropism
• Thigmotropism is the
growth response of a
plant to touch
• When the plant comes
into contact with an
object, it has the
tendency to twist or
wrap around a tree, up
the side of a house or
on a fence
The Common Phyla of the Animal
Kingdom
• 1. There are 9 major invertebrate (no backbone) phyla: (from simple
to complex)
• Porifera (sponges)
• Radiata (Jellyfish)
• Platyhelmeminthes (flatworms)
• Nematoda (round worms)
• Rotifera (rotifers)
• Mollusca (mollusks—clams, oysters)
• Annelida (segmented worms)
• Arthropoda (BIGGEST GROUP! insects, etc…exoskeleton)
• Echinodermata (starfish, et al.)
• 2. There is one phylum of vertebrates (backbone), Chordata.
Chordates have a spinal column and nerves to help it sense. These
are usually higher order animals.