<p>The Lac Operon basically involves an inducible enzyme, while the trp operon involves a repressor enzyme. The Lac Operon is involved in E. Coli, as well as trp. The TRP operon produces the amino acid tryptophan continuously, but then eventually, it acts as a co repressor, and binds to the inactivated repressor and turns it on seizing production. The Lac operon is originally shut off, because a repressor protein is occupying the operator. So no, lactose is produced until some lactose that was already made, minds to the repressor, activating it, it moves--RNA binds, and transcription begins. (easy question, but thanks).</p>
<p>the lac operon produces "inducible enzymes", meaning that the presence of the substance (lactose), inactivates the repressor that is normally produced by the lac operon which inhibits the RNA polymerase to transcribe the genes responsible for the lactose enzymes. </p>
<p>the trp operon works in the opposite way...the presence of tryptophan inhibits the production of the enzyme that produces tryptophan...therefore they are known as "repressible enzymes"</p>
<p>what is the hormone that lines the uterine walls and where is it produced?</p>
<p>"3. What is the cell that is the precursor to the primary speratocyte and what is the cell that is the precursor to the primary oocyte?"</p>
<p>(previous question..someone answer cuz i really want to know)</p>
<p>progesterone and estrogen help regulate that cycle. mainly its progesterone that lines the uterine walls. FSH also helps as well in positive/negative feedback loops to control progesterone and estrogen levels.</p>
<p>progesterone is produced in the ovary</p>
<hr>
<ol>
<li>What is the enzyme found in mucous used to kill pathogens?</li>
<li>What are various methods of learning?</li>
<li>What is the cell that is the precursor to the primary speratocyte and what is the cell that is the precursor to the primary oocyte?</li>
</ol>
<hr>
<p>I dunno the curve vs. the AP. it changes really year to year, but the curve for sat ii e is supposed to have an easier curve than the m test. which one are you taking?</p>
<p>estrogren increases the lining of the uterine wall, in case of fertilization</p>
<p>Kirby:
1.proteolytic
2.imprinting, habituation, Fixed action pattern, observational learning...</p>
<h2>3.I'm flummoxed--watch it be something extremely simple. I mean are you talking about the haploid gametes of meiosis II?</h2>
<p>Haha, I heard just the opposite. I head the SAT II M has a better curve.</p>
<ol>
<li>i was thinking of lysozyme at the time.</li>
<li>classical conditioning and operant conditioning, habituation, imprinting</li>
<li>spermatogonium and oogonium</li>
</ol>
<hr>
<p>meh, i still dunno which one to take yet.</p>
<p>its lysozme</p>
<p>i guess its open questions again...</p>
<p>Sorry, going back to the uterine lining, progestrone has a more profound effect on the thickening and stimulation of mucus secretory cells in the endometrium, compared to estrogen. (I'm pretty sure, 'twas a year ago)</p>
<p>Also, not just the "ovary" but more specifically the corpus leutum releases the hormones. (left over of the follicle after ovulation occurs from burst of Leutenizing Hormone (LH) from the anterior pituitary-stimulated by GnRH)</p>
<h2>How so? lysosomes are involved in intracellular digestion; they break up food vacuoules, etc. To my knowledge--proleotyc enzymes are located in mucus.</h2>
<p>Open question.</p>
<p>lysosomes are involved in intracellular digestion....lysozymes are completely different. They are the enzymes that are in human secretions (tears, mucus) that kill bacteria.</p>
<p>Question(s):
1.__<strong><em>bind with</em></strong>___by hydrogen bonds in a double helix of DNA.
2.How is enzyme activity regulated, or inhibited.
(fairly easy questions).</p>
<p>the bases of the DNA are bound together by hydrogen bonds
enzymes can be inhibited by: change in pH and temperature, inhibitors (competitive: another similarly shaped molecule binds to the substrate of the enzyme, allosteric inhibitor, which binds to the enyzme and induces the enyzme's inactive form, noncompetitive inhibitor, where a molecule binds to teh enzyme and changes its shape</p>
<p>what's a barr body</p>
<h2>Enzymes: yes, as you mentioned are degraded by a low pH and and extreme temperatures. Yes, they are also inhibited by allosteric inhibitor, and competitve and noncompetitive inhibitor.</h2>
<p>Purines bind with Pyrimidines: A H-bonds with T and G H-bonds with C.</p>
<h2>Purines have a single ring (T and C), where Pyrimidines have a double ring (A and G).</h2>
<h2>Barr Bodies are basically inactive X chromosomes--basically, they have the power to shut off sex linked traits, if located on the chromosome.</h2>
<p>Question:
1.Describe three different shapes of bacteria.
2.Describe the three means of motility in bacteria.</p>
<p>3 different shapes of bacteria: spherical (cocci), rodlike (bacilli), spirals(spirilla)</p>
<p>flagella, corkscrew motion, gliding through slimy material they secrete</p>
<ol>
<li>what is the differnece between a polyp and a medusa, and what phylem do they belong to?</li>
<li>which type of cell release histamines? </li>
</ol>
<p>haha looks like just me and you ivy...I think i learned alot from this game</p>
<h2>The medusa and polyp are both found in cnidaria which are basically jellyfish and squid. The Medusa is a bell shaped body, while the polyp--I'm gonna go out on a limb and assume it has something to do something with tentacles and an oral groove. If you look at a hydra with its nematocytes. If you want, you can elaborate.</h2>
<h2>Histamines are released by one of the cells during/prior an inflammtory response. I'd think it'd have to be a form of a platelet, but prothrombin and such don't do that. Something called a "bast cell." I don't think it's so much important to know what cell exaclty, just it's purpose; allergic reactions are a result of an influx of histamine.</h2>
<p>yeah, ron I'll catch you later tonight--ish. It doesn't matter if it's just you and me. I mean, we're getting a lot done--and I'm sure other people will come.</p>
<h2>Oh, my fault, the Medusa and Polyp are specific to Cnidaria--I was correct, but octupus' and and squids are not in the cnidaria phyla, but rather in the phyla mollusca. So, the medusa and polyp only pertains to Jellyfish and Hydra.</h2>
<p>Question(s):
1.What is a ganglia?
2.Diploblastic vs. Triploblastic germ layers.
3.What defines a chordate?
4.How was the ozone layer formed.
(fairly easy).</p>
<p>medusa is when the tentacles go downward (jellyfish); polyp is when the tentacles point upwards (hydra)</p>
<ol>
<li>ganglia is a cluster of nerve cells</li>
<li>diploblastic..having 2 germ layers (ecto+endoderm); eg. cnidarians (animals with radial symmetry)
triploblastic-3 germ layers (ecto+meso+endo)</li>
<li>a chordate has a notochord (spinal column)</li>
<li>The ozone layer is formed when O2 becomes ionized by radiation and forms O3.<br></li>
</ol>
<p>What is the difference between true fungi and oomycota?
how do fungi reproduce
what is the difference between a gametophyte and sporophyte?</p>
<h2>Yes, for four you could have also stated that in the primitive atmosphere, autrophic bacteria such as cynobacteria developed, the oxygen formed as a byproduct and led to the formation of the ozone layer--blocking UV light.</h2>
<p>1.A True fungi im assuming is one that is is either an aciomycota or a mioxymycota (spelling is probably way off);one lives in cellular slime mold, and the other in a plasmodial slime mold. True Fungi im assuming are the "neo" fungi that inhabit the land, without needing to be submerged in water like an oomycota. (similar to the bryophyta vs. tracheophyta).
2.Fungi reproduce by fragmentation, budding--using filaments called "hyphae." Also, they have asexual spores called conidia and sporoginia.</p>
<h2>3.Gametophyte is haploid, and sporophyte is diploid. The sporophyte doesn't the insemination, and gametophyte is I believe fertilized.</h2>
<p>Question(s):
1.Why does the level of FSH decrease and remain at a relatively low level during the LH phase of a menstrual cycle?
2.What is tropomyson?</p>