Download biology taks “must knows”

BIOLOGY TAKS “MUST KNOW”
1. Cellular Processes
Diffusion – To move from a low to a high concentration until homeostasis or equilibrium is met.
Osmosis – Diffusion of water from a high to a low concentration.
In the picture below there is 98% water inside and 95% water outside. Therefore the balloon will
shrink because water moves from a high to a low concentration until equilibrium is met.
Picture by TEA
If a cell is placed into salt water it will shrink…remember salt sucks! If a cell is placed into
100% pure distilled water it will swell!
2. Cell Parts & Functions
Chloroplast – organelle in a cell that uses sunlight to make food. Plants have these not animals.
*Mitochondria* – organelle in a cell that uses food to convert it into ATP. ATP is the form of
energy that ALL living things need to survive, including plants. Plants make their own food
from the sun, but they still need mitochondria to convert it into ATP. In animals, muscle cells
have a lot of mitochondria!
Cell Membrane/Plasma Membrane – organelle that surrounds all cells. It is the barrier that
allows things in & out of a cell. This organelle maintains homeostasis within the cell. In the
picture above, the balloon represents the cell membrane.
Cell Wall – all cells have a cell wall EXCEPT ANIMALS. Animals do not have a cell wall.
Plants, Fungi, Protista, & Bacteria all DO have cells walls. The function is for support &
protection.
Nucleus – the organelle where DNA is stored…bacteria are the only living cells that do not have
a nucleus, but they still have DNA. DNA is the code to make proteins.
Ribosome- the organelle where proteins are made.
http://summit.k12.co.us/schools/shs/computer/tkelley/types.html
3. Photosynthesis/Cellular Respiration
These are EXACT OPPOSITES!
Photosynthesis – the process of taking sunlight (solar energy) and converting it into food
(chemical energy). The food plants make is called glucose C6H12O6. This process occurs in
the CHLOROPLAST. Plants take in water & carbon dioxide and make food & release oxygen.
Water + CO2 + Sun Food + O2
Cellular Respiration – the process of taking food or glucose and converting it into ATP (another
form of chemical energy). This occurs in the MITOCHONDRIA. We eat food, breath oxygen
and blow out carbon dioxide & water vapor in order to get energy to survive. All living things
use this process. Yes the water that went onto the plants you ate is being blown back into the
atmosphere as water vapor.
Food + O2 Water + CO2 + ATP
Photosynthesis & Cellular Respiration are exact opposite reactions (a cycle) except solar energy
becomes chemical energy (ATP).
4. Viruses
Viruses are NOT a cell like bacteria are! This is because they need a host cell to reproduce…
they need to take over another cell and get it to do it for them. A real cell has the ability to
reproduce on its own. Viruses cannot do this! One thing viruses do have in common with cells
is they use DNA/RNA as their genetic material. Examples of viruses are influenza (flu), the
common cold, small pox, West Nile, warts, hepatitis, HIV, etc. There are vaccines for certain
viruses that can prevent getting infected, but once a viral infection has occurred only the immune
system can get rid of it. You CANNOT take ANTIBIOTICS for a viral infection. Antibiotics
can only cure bacterial infections! One last thing that students MUST know is that HIV attacks
KILLER-T CELLS!
http://www.worsleyschool.net/science/files/virus/page.html
5. Bacteria
Benefits: Bacteria help with digestion. For example, you have E.coli bacteria (the good kind)
that live in your intestines that help you with digestion. The reason eating yogurt while taking
antibiotics is good is because it replaces the bacteria that were killed by the antibiotics. Yogurt
has live bacteria in it that is good for you & your digestive system. Another example is cows.
Cows eat plants so they have to digest cellulose. The only way that the cellulose can be digested
is by the bacteria in their digestive system. If a veterinarian gives a cow antibiotics, they must
replace the bacteria or the cow will starve to death.
Disease: Antibiotics can be taken for bacterial infections. Examples of bacterial infections are
strep throat, tetanus, tooth decay, etc. When you have an infection of any kind you may
experience fever, swelling, rashes, and an increased WHITE blood cell count. This is your
immune systems way of fighting it off.
6. DNA (Deoxyribose Nucleic Acid)
DNA is the genetic code to make proteins. You are one big protein. Its shape is a double helix
or twisted ladder. DNA stores genetic information by the order of the NITROGEN BASES in
the middle (or the steps of the ladder). If the order of the nitrogen bases changes, a mutation
occurs and the correct protein may not be made. The nitrogen bases are adenine (A), thymine
(T), cytosine (C), & guanine (G). “A” matches with “T”. “C” matches with “G”.
http://members.cox.net/amgough/Fanconi-genetics-genetics-primer.htm
http://genome.imim.es/courses/Madrid04/exercises/ensembl/index.html
DNA Replication – the process of the DNA making a copy of itself before the cell divides. The
DNA will unzip and a new side will be added to each old side. So each new DNA strand will be
part old and part new.
Picture by Wikipedia
7. Protein Synthesis
There are a series of steps in order to make a protein. Proteins are made in the ribosomes of the
cell. The DNA holds the code to make the protein, but the DNA cannot leave the nucleus. The
process of getting the code from the DNA to the ribosome is called TRANSCRIPTION.
Transcription is step 1: RNA copies the DNA inside the nucleus and takes it to the ribosome.
RNA differs from DNA in that it does not have the nitrogen base called thymine (T). Instead of
“T’ RNA has uracil (U). So in RNA “A” matches with “U” and “C” matches with “G”.
http://genome.imim.es/courses/Madrid04/exercises/ensembl/index.html
Step 2 is called TRANSLATION – the actual assembly of the protein. Translation is where
RNA takes the code to the ribosome to be decoded into a protein. Every 3 nitrogen bases
(codon) codes for 1 amino acid. A protein is a chain of amino acids. The students must be able
to read a codon chart. The words in the chart below are amino acids.
Picture by TEA
A mutation has occurred to the second nitrogen base. It has mutated from a “G” to a “C.” The
first protein would have a chain of Arginine-Serine-Serine. AGA = Arginine UCG = Serine
AGU = Serine. The mutated protein would have a chain of Threonine-Serine-Serine.
ACA=Threonine UCG=Serine AGU=Serine. Because the sequence of amino acids has changed,
the function of the protein will change…it will not be able to do its job!
8. Evolution – Change Over Time
Evolution is not a high stakes concept for RRISD. There is much the students need to know
about evolution. Some common vocabulary is Charles Darwin, Common Ancestor, Fossil
Record, Similarities in Embryology, Natural Selection, Homologous Structures, Analagous
Structures, Speciation, Adaptation, etc. The students need to also understand that the more
similar the DNA, the more closely related the species.
9. Genetics
Basic Vocabulary:
Allele, Dominant, Recessive, Homozygous, Heterozygous, Punnett Square, Chromosome,
Pedigree, Sex-Linked Traits
Picture by TEA
What trait will most likely be observed in all offspring of the above set of parents?
A Green feathers (this is the correct answer)
B Yellow feathers
C Long beak
D Short beak
http://www.accessexcellence.org/RC/VL/GG/pedigree.php
http://www.macalester.edu/psychology/whathap/UBNRP/visionwebsite04/twotypes.html
10. Classification of Organisms
Taxons: Kingdom (large group), Phylum, Class, Order, Family, Genus, Species (small group)
All organisms have a two-part scientific name. The first part is the Genus and the second part is
the Species. For example Homo sapien; humans are classified by this name. Homo is the Genus
and sapien is the Species. If two different species have the same Genus, then they are closely
related. For example, Felis concolor is the mountain lion Felis domesticus is the domestic cat.
Background Vocabulary:
Prokaryote—cell without a nucleus or membrane-bound organelles (ONLY BACTERIA)
Eukaryote—cell with a nucleus and membrane-bound organelles (Protista, Fungi, Plantae, &
Animalia)
Unicellular—of one cell or single-celled
Multicellular—of many cells; each cell has a special function
Autotroph—(Producer) - makes its own food
Heterotroph—(Consumer) - cannot make its own food; must get it from elsewhere
Kingdom Archaebacteria
Prokaryote
Cell Walls WITHOUT peptidoglycan
Unicellular
Live in extreme conditions
Kingdom Eubacteria
Prokaryote
Cell walls WITH peptidoglycan
Unicellular
Live in normal every environments
Examples: Streptococcus or Escherichia coli
Kingdom Protista
Eukaryote
Cell Walls—various types
Most are unicellular
Some are multicellular
“Junk Drawer” or “Catch-all” Kingdom
Examples:
Amoeba, euglena, paramecium, diatoms, algae, giant kelp
Kingdom Fungi
Eukaryote
Cell Walls made of chitin
Most multicellular; some unicellular
Heterotroph
Examples: mushrooms, yeasts, athlete’s foot, ringworm
Kingdom Plantae
Eukaryote
Cell Walls made of cellulose
Have chloroplasts for photosynthesis
Large water vacuole
Multicellular
Autotroph
Examples: mosses, ferns, evergreens and flowering plants
Kingdom Animalia
Eukaryote
NO Cell Walls – The only Kingdom without Cell Walls!
NO Chloroplasts
Multicellular
Heterotroph
Examples: Sponges, worms, insects, fishes, mammals
11. Ecology (Energy Flow)
Energy flows in one direction in an ecosystem. It starts with the sun, then goes to the
producers/autotrophs (ex. plants), then goes to the consumers/heterotrophs (ex. humans).
Basic Vocabulary:
Omnivore – consumer that eats both plants & animals
Herbivore – consumer that eats only plants
Carnivore – consumer that eats only meat
Decomposer – breaks down dead or decaying matter so matter can recycle within the ecosystem.
The two largest decomposers on Earth are bacteria and fungi.
Trophic Level – Each step if a food chain.
10% Rule – Only 10% of energy or biomass is passed from one trophic level to the next. 90% is
transferred to heat.
See next page…
Food Chain – The arrow points to the mouth that is being fed. The arrow is pointing in the
direction the energy flows. Also remember that the sun is the main energy source!
Food Web – many food chains together…Remember the arrow points to the mouth that is being
fed. In this food web the plants are on trophic level 1 and are the producers of the food web. An
example of a primary consumer would be the rabbit. An example of a secondary consumer
would be the fox.
http://king.portlandschools.org/files/houses/y7/animalmaineia/files/species/rdovefi/foodweb/Foo
dwed.html
Ecology Pyramids – A different way to view a food chain.
http://www.princetonecology.org/id35.html
http://www.arcytech.org/java/population/facts_foodchain.html
12. Ecology (Symbiosis)
Symbiosis is a relationship where two species live closely together. There are three kinds.
Mutualism (+ +) both organisms are benefiting. (a bee & a flower.)
Parasitism (+ -) one organism is benefiting and the other is being harmed. (a tick & a dog)
Commensalism (+ ≠) one organism is benefiting and the other is neither helped or harmed. (an
orchid in a tree…an orchid is a flower…it is benefiting because it gets a place to live & is
propped up to more sunlight…the tree is not helped or hurt because the orchid is not taking any
nutrients from the tree.
13. Plant Adaptations
Survival of the fittest…evolution…the organisms that have “strong” genes to survive their
environment will reproduce…the “weak” organisms will die and not pass on their genes.
Tropical Rain Forest – big broad leaves under the canopy to fight for sunlight
Desert (arid/dry climate) – reduced or small leaves to prevent water from escaping out of the
stomata (the holes for gas exchange under the leaves); the stomata are also closed during the day;
cacti also have a thick cuticle (wax covering of leaf) to prevent water loss as well; cacti also have
an extensive fibrous root system to absorb water fast.
Tundra (cold climate) – plants have a thick cuticle (wax covering of leaf) for insulation & also
grow close to the ground to stay warm.
14. Body Systems
Circulatory System
Heart, Veins, Arteries and BLOOD!
Main function: transports or delivers or distributes nutrients, water, white blood cells,
respiratory gases, and wastes throughout the body. Hemoglobin is the protein in the blood that
carries oxygen to body cells. We have a closed-circulatory system meaning the blood circulates
within vessels. Clams have an open-circulatory system where blood baths tissues in the
cavities called sinuses.
Nervous System
Brain, Spinal Cord, Neuron & Synapse
Main function: Sense internal & external stimuli (the 5 senses: sight, smell, taste, hear, touch) &
storing memories…thinking!
Neuron
http://www2.cedarcrest.edu/academic/bio/hale/bioT_EID/lectures/tetanus-neuron.html
Endocrine System
Glands and Hormones
Main function: To maintain homeostasis by delivering messages throughout the body with
hormones. (Feedback loops- like the air conditioner).
Organs: Hypothalamus, Pituitary Gland (main gland), Parathryoid Gland, Thymus Gland, Pineal
Gland, Adrenal Gland, Thyroid, Pancreas, Ovary and Testes.
Skeletal System
Bone; bones are held together at joints with ligaments.
Main function: structure & support, movement, & to make red & white blood cells in the bone
marrow.
Muscular System – Muscle cells have a high number of mitochondria to convert food into
ATP/energy!
3 kinds of muscle cells: skeletal, smooth, & cardiac
Main function: Movement. For every muscle there is an opposing muscle group for extension &
flexion. Muscles are attached to bones through ligaments. The muscle shortens, pulls on the
bone, & the limb moves.
http://www.nambourshs.qld.edu.au/curriculum/hpe/hpes/online/biomech.htm
Respiratory System
Lungs, Alveoli (little grapes, air sacs)
Main function: diffusion of oxygen and carbon dioxide gas into and out of the blood.
Alveoli
http://www.cartage.org.lb/en/themes/Sciences/LifeScience/GeneralBiology/Physiology/Respirat
orySystem/HumanRespiratory/HumanRespiratory.htm
Urinary/Excretory System
Kidneys (Nephron is the filtering device) & Bladder
Main function: filters your blood through diffusion.
http://www.foxriverwatch.com/kidney_cancer_pcbs_intro.html
Digestive System
Mouth –(chemical & mechanical digestion begin here), Pharynx, Esophagus, Liver, Gall
Bladder, Stomach, Rectum, Pancreas, , Small Intestine (microvilli absorb nutrients), Large
Intestine (absorbs water)
Main function: diffusion of nutrients and water into the blood; produces enzymes that aid in
breaking down substances to be absorbed for the body’s growth & repair.
http://www.bayfrontgi.com/patient_education.asp
Integumentary System – Skin, Hair, & Nails
Skin layers are Epidermis, Dermis and Hypodermis
Main function is to protect you, helps keep you cool with sweat, & it is a major sensory organ for
touch.
Reproductive System
Female and Male reproductive parts…
Main function: to make gametes (or sex cells) to have offspring and to produce hormones such
as testosterone and estrogen (connection to endocrine system b/c of the hormones).
Sexual reproduction- two parents each provide half the genetic material resulting in
offspring (first cell = zygote) with characteristics of both parents. Gametes (or sex cells) are
made through a process called Meiosis (PMAT1 & PMAT2). This method of reproduction
increases diversity because of crossing-over or gene shuffling.
Asexual reproduction- single parent produces offspring that are genetically identical to
the parent…an example is binary fission in bacteria.
Lymphatic System
Lymph Nodes & Spleen
Main function: to pick up fluid that has leaked into surrounding tissue and filter microorganisms
with the lymph nodes. Works closely with the immune system.
Immune System (Lymphocyte means White Blood Cell)
B Lymphocytes make plasma cells that make antibodies (Humoral Immunity), T-Cells kill
infected or abnormal cells of our own (Cell-Mediated Immunity)
Main function: Fights off disease and cancer.
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A vaccine is a small amount of weakened or dead pathogens that allow the body to
respond and build up memory cells so the next time exposure occurs the body has a huge
army of defense ready. There are vaccines for different kinds of bacteria and viruses.
Anything that causes disease is called a pathogen. You can take antibiotics to cure a
bacterial disease, but not for a viral disease. Bacteria produce toxins or poisons that
can hurt your body. Your humoral immunity is designed to produce B lymphocytes that
produce plasma cells that produce antibodies that bind to the antigens on the pathogen to
deactivate them so a macrophage can eat it.
If a virus, protista, or fungus gets inside one of your cells or you have cells that
turn into cancer your cell-mediated immunity will kill your cell that
is infected or is growing “out of control” aka cancer.
The T-cell made a hole in your bad, infected, or cancerous cell.
HIV attacks T-cells!
www.jdaross.cwc.net/cellmediated_immunity.htm