AP Biology Review Thread

Test Preparation AP Test Preparation
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<p>the endosymbiotic theory states that organelles such as mitochondria, chloroplasts, and possibly even nuclei were once prokaryotes living inside other prokaryotes. evidence that supports this theory are the similarity between the plasma membranes of the organelles and the larger cell, organelles divide much like binary fission, and the organelles contain DNA similar to that of a prokaryote. </p>

<p>Describe the main characteristics of earth’s terrestrial biomes.</p>

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<p>Question: What characteristics define an animal?</p>

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<p>“Question: What is the endosymbiotic theory, and what is a piece of supporting evidence for the theory?”</p>

<p>symbiotic theory states that prokaryotes may have come together to form eukaryote. The reason is that each prokayotes probably were benefiting in some way (hence symbiotic theory).
The theory states that mitochondria and a large prokaryote came together, and later chloroplast became apart of this “alliance.” without the formation of this “alliance” complex organisms like humans and plants would not exists.</p>

<p>Evidence have been found giving credibility to this theory. They are:</p>

<p>Mitochondria and chloroplast both have:
their own DNA
double bilayer (two plasma membranes)
Replicate DNA that differs with the timing of the overall host cell.</p>

<p>I think im missing some parts.</p>

<p>EDIT: </p>

<p>Question: What characteristics define an animal?</p>

<p>Not sure if this is right but.</p>

<p>Coleom- fluid filled compartment which becomes an area of the body that hold the circulatory system, lungs, digestive system etc.
Some organisms do not have a coleom and are called Acolemate. Others have a teansport system and no other system and are called pseudocolmate.</p>

<p>bilateral symmetry- both sides of the body are mirror images. Some animals have no symmetry, or radical symmetry</p>

<p>demostromes and pseudostromes-
demostromes- first hole becomes the mouth, second hole becomes the anus
pseuostromes - first hole becomes the anus</p>

<p>cephalization- anterior and posterior part of the body. anterior contains the nerves and posterior contains the digestive system. This makes fleeing easier for organisms</p>

<p>multiple layers -endoderm, mesoderm, ectoderm become skin/nerves, digestive system, and bone/blood respectively.</p>

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<p>

</p>

<p>marine
largest
temperature varies little
provides most of earth’s food and oxygen
marine life</p>

<p>deciduous
plants drop leaves in winter
rich soil due to decomposition
verticle stratification- plants are characterized by varying heights
animals that hibernate in winter</p>

<p>desert
little rainfall, grasses can’t survive
most extreme temperature fluctuations
small, annual plants that are born after rain and die in a few weeks
rodents, insects, some birds</p>

<p>tudra
little rainfall
permanently frozen subsoil called permafrost
polar bears, wolves</p>

<p>taiga
cold winters
lots of lakes/ponds
largest biome after marine
heavy snowfall
tree branches point downwards
moose, porcupines</p>

<p>Question: Describe the process of gene cloning (also known as transformation)</p>

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<p>@ darkflame
i may be wrong but isn’t the mesoderm responsible for blood and bones? And then the ectoderm becomes the digestive system?</p>

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<p>Re Darkflame: yes. You went into the specifics of development. Also, all animals are multicellular, heterotrophic eukaryotes. Most animals reproduce sexually and the diploid stage is dominant. Animal cells lack cell walls and are held together by structural proteins like collagen. Although not all animals have them, nervous tissue and muscle tissue are unique to animals.</p>

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<p>Can someone who is a pro at reproduction explain LH, FSH, estrogen, and progestone and their roles in a complete ovulation and mentral cycle. Also compare and contrast the two cycles</p>

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<p>@motivated</p>

<p>you’re right.
Ectoderm= nervous system, skin, hair, nails
Endoderm= digestive system
Mesoderm= bones, circulatory system, connective tissues, muscles, reproductive system, urinary system</p>

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<p>Endoderm becomes the lining of the digestive system.</p>

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<p>^your all right ill correct it right now. Thanks</p>

<p>Edit: it wont let me edit that post -_-</p>

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<p>@DarkFlame: doesn’t matter. It’s a study board- as long as we’re learning, right? =]</p>

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<p>@marcus</p>

<p>The Menstrual Cycle</p>

<p>Follicular phase: Follicle Stimulating Hormone (FSH) from the anterior pituitary stimulates the follicles in the ovaries.
Ovulation: lutenizing hormone (LH) causes the secodary oocyte to jump out of the ovaries. If fertilized:
-Fertilization (When a mommy and daddy love each other very much…)
-Cleavage (zygote starts dividing, becomes ball of cells)
-Blastocyst</p>

<p>Luteal Phase: corpus luteum forms from the follicle left behind by the oocyte and secretes estrogen and progesterone, which causes the thickening of the uterus.
Menstruation: extra lining is shed when there’s no baby.</p>

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<p>Ovarian Cycle = the events in the ovary</p>

<p>When there are low levels of estrogen and progesterone, the hypothalamus releases GnRH. This stimulates the anterior pituitary to release FSH and LH. FSH then stimulates the development of a follicle and egg. The developing follicle releases estrogen, prompting the hypothalamus to again release GnRH. This makes the anterior pituitary release more LH, which triggers ovulation (the release of the egg and rupture of the follicle). After ovulation, the corpus luteum (the remnants of the ruptured follicle) is stimulated by this LH and secretes even more estrogen and progesterone. This makes the uterine lining, the endometrium, thicken. This ends the production of FSH and LH from the pituitary. Now, one of 2 things will happen:</p>

<p>1) The embryo does not implant. The corpus luteum deteriorates, and so the endometrium does too. They are sloughed off in menstruation. </p>

<p>2) The embryo does implant. Remember, the hypothalamus is not secreting GnRH anymore after the thinkening of the endomentrium, and FSH and LH levels have gone down. However, t maintain the uterine wall, the embryo releases HCG to maintain the endometrium.</p>

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<p>can someone answer this question?</p>

<p>Explain how the immune system achieves 3 of the following?

  1. Provides an immediate nonspecific immune response
  2. Activates T and B cells in response to an infection
  3. Responds to a later exposure to the same infectious agent
  4. Distinguishes self from nonself</p>
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<p>good luck guys.</p>

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<ol>
<li>the nonspecific immune responses include skin, mucous, natural killer cells. These are nondescriminatory factors that aim to keep any viruses and bacteria from entering the body.</li>
<li>helper t cells are what activate B and T cells. B cells are activated if an antigen is found in the blood. once an antigen is found the B cells undergo clonal selection and make copies of plasma cells and more B cells. plasma cells secrete specific antibodies and the andibodies can get rid of a pathogen by either agglutination, neutralization, precipitation, or activating compliment proteins. however, if an antigen is displayed by an already infected tissue cell, macrophages signal helper T cells, with interleukin I believe, to have cytotoxic T cells get rid of the pathogen. The cytotoxic T cells introduce a chemical that causes the macrophage to lyse and in effect kill the infected cell.</li>
<li>When B cells undergo clonal selection they create both plasma cells for now and more B cells. the extra B cells, I believe, serve as the memory cells which allow for a much quicker reaction to the same infectious agent. these memory cells are usually stored in the lymph system.</li>
<li>I don’t quite remember specifically how the body detects self from nonself, but I know that in autoimmune diseases such as lupus and rheumatoid arthritis, the cells cannot detect self from nonself and end up harming self cells.</li>
</ol>

<p>The immune system is a vast and complicated system, I only covered what I remember.</p>

<p>Name the branches and defining characteristics of each branch (clade) in the phylogenetic tree of animals. For example: Ctenophora differs from Porifera because they are eumatozoan.</p>

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<p>That was a very good exp. of the ovarian cycle! I also found this diagram if anyone is interested since diagrams do help a person learn more extensively.</p>

<p>[Campbell</a>, Biology, Seventh Edition - eBook Login](<a href=“http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714646027.jpg]Campbell”>http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714646027.jpg)</p>

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<p>immune system diagram</p>

<p>[Campbell</a>, Biology, Seventh Edition - eBook Login](<a href=“http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643003.jpg]Campbell”>http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643003.jpg)</p>

<p>nonspecific responses diagrams
[Campbell</a>, Biology, Seventh Edition - eBook Login](<a href=“http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643006.jpg]Campbell”>http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643006.jpg)</p>

<p>[Campbell</a>, Biology, Seventh Edition - eBook Login](<a href=“http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643009.jpg]Campbell”>http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643009.jpg)</p>

<p>[Campbell</a>, Biology, Seventh Edition - eBook Login](<a href=“http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643010.jpg]Campbell”>http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/big/3714643010.jpg)</p>

<p>overview of specific responses</p>

<p>[Campbell</a>, Biology, Seventh Edition - eBook Login](<a href=“http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/thm/3714643020.jpg]Campbell”>http://wps.aw.com/wps/media/objects/1668/1708348/ebook/fig/thm/3714643020.jpg)</p>

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<p>Thanks for the links, marcus! Unfortunately, it looks like you have to buy access to the site, but for those who have an account I’m sure it will be helpful.</p>

<p>Question: What is transformation (also known as gene cloning)? How is it used?</p>

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<p>Transformation: Bacteria pick out DNA from surroundings. Uh, I guess it creates variations??</p>