Last Minute AP Biology Help.

Test Preparation AP Test Preparation
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<p>Lol, again correct. The cycles are simple but I forgot the name. You must be a bio nerd (I am ambivalent towards it. I'm more of a math/chem person). That is one heck of a question that I can only partially answer.</p>

<p>A: Nine animal phylums, right? (They are called something else in plants...).</p>

<p>We have chordates (us) who have lungs and and a chambered (#depends) heart. I'm too lazy to explain the rest (heart beats, closed circulatory system, etc...).</p>

<p>Umm, planarians are flatworms, and they probably have a basic gas exchange system. Diffusion through skin?</p>

<p>Echinoderms are the sea stars and others. I don't remember much about them. Oh well.</p>

<p>Cnidarians are basic jellies, hydras, and such and probably just use diffusion.</p>

<p>Arthopoda are insects/lobsters. They have open systems (hemolymph) and bathe their organs in it.</p>

<p>Annelidia are segmented worms and have that weird ringy closed circulatory system.</p>

<p>Rotifera is the weird in-between one. I don't remember much about them.</p>

<p>Molluska (or whatever it is called) is made of clams and cephelopods. I don't know about their system. </p>

<p>I need to look up the rest. Oh, nematoda and the weird ctenophora one. Can you answer about their gas exchange system for me?</p>

<p>Q: The previous behavior question, asking you to describe the different kinds, such as habituation, instinct, learned, stimulus-response, etc...</p>

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<p>Nematoda: They don't have circulatory systems either, so they exchange gases by simple diffusion. </p>

<p>As for Mulluscs, I remember that some marines ones have gills, which they use in the exchange of gas. </p>

<p>I haven't heard of the other weird phylum ;/</p>

<p>Q: The previous behavior question, asking you to describe the different kinds, such as habituation, instinct, learned, stimulus-response, etc...</p>

<p>Habituation, is when a harmless action is repeated a certain amount of times so that the animal learns to ignore the effects of it. [IE, if you keep on poking a dog, it will eventually learn to not respond to the poke]</p>

<p>Instinct, is something that doesn't need to be learned. An animal is usually born with certain instincts. </p>

<p>Fix-action pattern: Is an action, that when 'stimulated' by releasers, will be carried out to completion no matter what happens. [I remember an example from Barons book about birds who will care for even artifical eggs - because they resemble their own eggs]</p>

<p>Classical Conditioning: Pavlov's dog! ;] It's when an animal learns to associate a specific behavior with an action of their own. [IE, salivating when they hear the sound of a bell].</p>

<p>Operant Conditioning: An example is when mice learns to press a button to receive 'food'. I think this is sort of like a trial-error behavior. </p>

<p>Learning: This is when we learn to change our behavior based on past experiences.. [Can't rememeber how this one was explained exactly, but humans have the ability to learn.]</p>

<p>^ Those are the ones I remember, and what I remember of them. I think some of my explanations could do with more information though. </p>

<p>Q: Describe Cyclic phosphorlyation, and its benefits.</p>

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<p>Cool. Yeah, one's Pavlovian and the other from Skinner (what's the adj. form of that?). I will be off soon, maybe another question or two as it is 1:54AM here, though I go to bed regularly at 2:30.</p>

<p>A: Well, light hits photosystem II splitting water. The energized electrons from this are dropped down a small ETC, creating ATP. They then arrive at Photosystem I (I might be missing something here... Maybe light hitting pym I and re-energizing the e-?). Here they (e-'s) can either move to ionize NADPH (or whatever they do with that...) or can be moved back to the ETC (forgot the carrier. Starts with an "f") to create additional ATP. This can be continued indefinitely and is necessary as noncyclic phosphorlyation does not create enough ATP for the Calvin cycle to run its course.</p>

<p>Q: Describe the endomembrane system.</p>

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<p>A. It consists of all of the different cell organelles that are formed by double membranes, including the nuclear membrane, ER, Golgi complex, as well as peroxisomes, lysosomes and vesicles (I'm not sure if those last three are truly part of the system, but whatevs). The nuclear membrane encloses the chromatin, and has pores for RNA strands and ribosomes to exit. Its membrane is continuous with the ER, the sight of manufacturing for a variety of compounds, including hormones, lipids, and proteins (on the rough ER, spotted with attached ribosomes). Vesicles transport macromolecules to the Golgi Complex, where they are modified and transported to the outside of the cell for release or attachment to the plasma membrane. Peroxisomes have enzymes to break down certain poisons (H2O2), lysosomes function in intracellular digestion, and vesicles are used for transport throughout the cell as well as endo and exocytosis. Boo-ya!</p>

<p>Q. Briefly describe the process of muscle contraction.</p>

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<p>A. here goes nothing (all of u have definatly learned more then me)</p>

<p>SO the muscle contractions are controlled in the Central nervous system? There are also generations of action potentials that trigger this contraction and helps with the movement. This is a result of actin and myosin cross bridges. The muscle types are also a factor, there are skeletal, cardiac and smooth muscle tissues. The action potientials also create an electro chemical gradient i believe and it jumpes nodes (nodes of ranvier). The myofibrils i believe have like A-Bands and Z-Lines and the position in a picture can help you determine weather or not the muscle is contracted or at rest. Hmm there is also details about the enzymes, acetyle cholineesterase and acyetlcholine that help trigger and bind the receptors to the receptor sites to initiate the process.</p>

<p>er a nyone want to reanswer lol, i know im all over the place but if that were a real frq i would write all that in the outline then fix up the info.</p>

<p>Q: Describe the cell cycle, include breif descriptions of mitosis and meiosis.</p>

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<p>A: The cell cycle consists of G1, S, G2 and M phases. G1 is the growth phase where the cell accumulates ample ATP and nucleotides in order to replicate its chromosomes. S is synthesis, where the cell copies its chromosomes in preparation for cell division. G2 is the second growth phase aimed at building up ATP to divide, as well as providing sufficient organelles and cytoplasm for the daughter cells. Cyclins build up during this phase and activate cyclin-dependent kinases. These CdKs then phosphorylate the nuclear membrane, leading to the M phase of mitosis, when the chromosomes separate to opposite poles of the cell. Finally, the cell undergoes cytokinesis (via a cleavage furrow in animals or a cell plate in plants). There is also another checkpoint during mitosis when the Anaphase promoting factors wait until all chromosomes are lined up on the metaphase before the individual sister chromatids start working their way up the spindle fibers toward the opposite poles. (my teacher really stressed the checkpoints, although I know that there was another one in there somewhere that I missed, so I guess I'd better review that...). In the process of meiosis, the cell undergoes two sets of divisions. In the first set, homologous chromosomes seperate to different cells. In the second set of division, individual sister chromatids seperate to different cells, resulting in four genetically distinct daughter cells in the haploid state, known as gametes. During prophase I, homologous chromosomes form tetrads and undergo a process of DNA exchange called crossing over. And yeah... I think I'm out.</p>

<p>Q: Name one hormone manufactured and/or released from each of the following endocrine glands, and identify its primary function: Anterior pituitary, posterior pituitary, pancreas, thyroid, and adrenal. (Include as many as you want if you know more than one, or other glands, for additional review)</p>

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<p>Anterior pituitary:
-Oxytocin: Breasts and uterus
-Antidiuretic hormone - Controls water in kidneys</p>

<p>Posterior pituitary:
-FSH: Sperm and eggs
-Leutenizing hormone: Sex organ growth
-Growth hormone: Growth
There are 3 more but I forgot them</p>

<p>Pineal:
-Melanotonin: Timing and stuff</p>

<p>Pancreas:
-Insulin: Lowers blood glucose
-Glucagon: Raises blood glucose</p>

<p>Thyroid:
-Triio-something (T3) and thyroxine (T4): Controls metabolic rate
-Calcitonin: Lowers blood calcium
-PTH: Raises blood calcium</p>

<p>Adrenal:
-Epinephrine and norepinephrine: Raises blood glucose, increases heart rate
-Glucocortisoid and minerocortisoid: Something</p>

<p>Ovaries:
-Estrogen: Womanliness.
-Progesterone: Uterine lining</p>

<p>Testicles:
-Testosterone: Manliness</p>

<p>Explain kidney structure and function.</p>

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<p>Maybe I'm wrong... but isn't Oxytocin and ADH the posterior pituitary? And I barely know anything about kidney so I'll let someone else take that one</p>

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<p>Oh right, I mixed up the anterior and posterior.</p>

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<p>A: Okay, if I remember right, the kidney has an outer and inner layer (cortex and something else). The outer layer has nephrons (tubules) where water (with crap in it) passes through. There are two kinds of nephrons. One is shallow and one is long, with a Loop of Henle (forgot the names of the nephrons). The process starts at Bowman's Capsule. Here certain ions dissolve in and out. I forget which ones. I remember that at the loop of Henle, the water becomes really concentrated with solutes. Okay, most ions dissolve out (reabsorbtion) at the proximal tube. Only NH3 and H ions are secreted. On the descending loop H2O is reabsorbed (making the solution concentrated). The ascending loop has two parts. The first allow for the reabsorbtion of NaCl. The second does the same, but through active transport. Then ions are reabsorbed at the distal tube while potassium and H ions are secreted. At the collecting duct salt, urea, and water are reabsorbed. The urea that is secreted keeps that are concentrated so nutrients can dissolve done the concentration gradient. </p>

<p>Yeah, I used my book a bit for that one :( </p>

<p>Q: Name three common chromosomal errors.</p>

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<p>A: I don't know if I'm understanding this question correctly:
Trisomy of the 21st chromosome= down's syndrome
XXY=Klinefelter's syndrome
Cri-du-chat syndrome is when you're missing a small piece of a chromosome (don't remember which one)
Turner's syndrome is I think just one X chromosome
Yeah... most occur during improper division of chromosomes in meiosis, known as nondisjunction.</p>

<p>Q: Explain fungal reproduction (I actually have no idea about anything about fungi, we skipped that chapter.)</p>

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<p>I meant like nondisjunction, translocation, etc...</p>

<p>A: I can't do that off the top of my head yet (I did read it...) and it is different for each phylum (actually called divisions) of fungi. I'll use my book so you'll at least have an answer.</p>

<p>The generalized life cycle is that mycelium fuse in plasmogamy and become dikaryotic (n+n) and then the nuclei fuse in karyogamy forming a diploid stage (2n). This undergoes meiosis and forms a spore producing structure (e.g. sporangium). These release spores (n) which germinate into mycelium (n).</p>

<ol>
<li><p>We have zygomycota (myco=fungi BTW), or zygote fungi. They are primarily haploids (n), and there are two mating types, + and -. When opposite mating type mycelia meet they merge into a hard diploid ball (still attached to the branch like mycelia) called a zygosparangia (2n). This creates a haploid (N) sporangia which releases haploid spores (n). These can either be genetically varied or identical, resulting in sexual or asexual reproduction respectively. The spores grow into new mycelia.</p></li>
<li><p>Second, we have ascomycetes, which form bowl shaped ascocarps. These form after plasmogamy and are dikaryotic. Each strand of an ascocarp is called a hyphae. The two nuclei in the hyphae ascus (the end of the hyphae) fuse into a diploid (2n) nucleus. These meiose into four haploid (n) nuclei, which undergo mitosis to form eight ascospores. These are then released by the ascocarp and germinate.</p></li>
<li><p>Third are the basidiomycete, which form the mushroom shaped basidiocarp AFTER plasmogamy. The dikaryotic mycelium become basidiocarps after they are triggered by some enviromental cue. These basidiocarps are lined with dikaryotic basidia which undergo karyogamy to become diploid (2n). These undergo meiosis to form four basidospores which then release and germinate.</p></li>
</ol>

<p>So the defining structure of each division forms after plasogamy, and is the division name minus mycete but with carp added to the end. The pieces of this structure (for the last two) are different (one uses the division name). The spores are the division name with spore at the end (minus mycete of course.)</p>

<p>Phew..... I hoped that helped!!!</p>

<p>Q: Describe the different plant hormones and how they control systems in the plant.</p>

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<p>(Doing this without my book so..yeah)</p>

<p>Auxins: Cause cell growth, and phototrophism. The auxin causes the plant cells to grow and thicken on the side of the plant not facing the light so that the plant will bend toward the light.</p>

<p>Gibberelens (sp?): Start the development of the seed. (??)</p>

<p>Ethylene gas: Causes ripening, will affect other fruit to begin ripening as well. </p>

<p>Q: Hardy Weinberg problem: If 9 percent of the population has green eyss, what percent is hybrid for brown eyes? homozygous for brown eyes?</p>

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<p>The gibberelins (sp?) also control growth to some degree, or at least I think they do. Also there is ascibic (sp) acid which counteracts gibberelins and auxin and stops growth. Now checking my book to be sure... They are gibberellins. We both missed cytokinins which form in the roots. When they are mixed with auxins, exposed cells divide. Thus they work with auxin (formed in the apical bud) to regulate growth. More auxin equals roots, and more cytokinins equal shoot buds. Oh, and it was spelled abscisic acid. </p>

<p>A: 42% hybrids, 49% homozygous. Math is easy :)</p>

<p>Q: What are the conditions for H-W equilibrium.</p>

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<p>Let's see...
1.Random mating
2.No gene flow: no migration of alleles into/out of population
3.No mutation
4.No natural selection??
5.Oh god. Environment constant??
That was unfortunate.. </p>

<p>Q:
Explain how the nerve cell operates, including the parts, what direction the charge travels, the resting voltage, and how it fires.</p>

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<ol>
<li>No selective breeding.</li>
</ol>

<p>A: Okay, I read this last weekend so this should be right. The nerve cell is made up of three main parts; dendrites, which receive signals, the cell body, and the axon, which transmits signals. The axon is covered in a Myleian (?sp.) sheath which protects and helps it pass along action potentials (at the nodes of the sheath). </p>

<p>The nerve cell is negative, around -70 units (V? mv?). It contains potassium ions which migrate out, and sodium ion which migrate in, but not very well as the cell membrane is not very permeable to Na, resulting in the negative charge. If a nerve cell is depolarized enough (-50 or so) by having their sodium channels open, a graded response, an action potential, an all-or-nothing response, occurs. It is essentially a reversal of polarity caused by the opening of voltage dependent sodium gates and the closing of potassium gates. The potassium gate then slowly opens, while a second sodium gate closes, preventing sodium from diffusing in. Potassium leaves causing an action preventing hyperpolarized undershoot. Once all the gates go back to normal the cell can receive another action potential.</p>

<p>As the positive ion diffuse down the axon (one way only. I forget why. Maybe because of the undershoot?) action potentials result down the axon. At a synapse they charge either goes across through a bridge, or the release of neurotransmitters are triggered. These bind to proteins on the postsynaptic cell and cause gates to open causing polarity shifts. </p>

<p>Most neurons are connected to many others and their sum response determines what happens (ie action potential in the axon or not). The severity of an action caused by a neuron depends on how frequently action potential occurs. There are also fast and slow twitch neurons. Whew...</p>

<p>Q: Describe oxidative chemiosmosis.</p>

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<p>Hey guys I hope that you don't mind if I join... my teacher, while super fun and exciting, didn't really teach us all that well and we aren't done with the book yet so I need as much review as I can get.</p>

<p>Um so oxidative chemiosmosis is via the electron transport chain in cellular respiration. The electrons are sucked down to the more electronegative things and then the most electronegative is oxygen which is at the end. This energy from the electron transport chain pushes the protons out the inner membrane of the mitochondria. A concentration gradient builds up and the protons diffuse back into the inner membrane through ATP synthase. This adds a phosphate to ADP which makes it ATP. </p>

<p>So basically the proton gradient and the electron transport chain is the chemiosmosis. (right?) </p>

<p>Q: Describe the steps in protein synthesis.</p>

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<p>Is there a chatroom?</p>

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<p>^We def. need a chatroom for the next few days, can someone set one up?</p>

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<p>Alright, tomorrow let's start it up, when the most people are on, and we'll keep it running for a couple of days.</p>

<p>edit: as some incentive I'll upload some past ap bio exams so whoever joins can get them (don't bother PMing me about them, not gonna email it to 100000 people)</p>