I Need help completing my cell biology homework, I have only


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I Need help completing my cell biology homework, I have only answered the first three questions (A, B, C), but I feel they need more work. Also, I have no idea how to answer D and E. For D I feel that I can draw that by myself, I just need explanation. ATTACHMENT PREVIEW Download attachment 2015 BIO 353 Cell Biology Homework Assignment 2 posted…docx BIO 353 Cell Biology 1. Read the assigned paper (Gustavsson et al.) on glycolytic oscillations in yeast. You might also wish to read the Mayevsky and Chance review paper but this is optional and will not directly help you with the questions below. 2. Once you read and understand the material in the paper, embark on completing the assignment by answering the following essay questions: A. NADH is an electron transporter that shuttles electrons from substrates to the mitochondrial electron transport chain. What how might allosteric control of glycolytic enzymes be used as a mechanism that could create oscillations in NADH? (5 pts) B. Why might this control mechanism involve both aerobic and anaerobic glycolysis? Cytoplasmic NADH vs. mitochondrial NADH: Which would show greater swings in oxidationreduction state and why? Propose a way in which you could experimentally observe this. (5 pts) C. Would you expect to see cyclic oscillations of ATP levels? Of pyruvate? Of reduced cytochrome c? Explain. Would you expect to see the ATP oscillations in phase or out of phase with the NADH oscillations? (5 pts) D. Draw a diagram that explains the feedback control processes involved in these oscillations. (9 pts) The diagram must be original (not a copy) and hand drawn, not using computer software. For example, the diagram could consist of a “cause and effect” cycle drawn as a circle with each step leading by an arrow to the next. This diagram should include at minimum: a. allosteric controlled enzymes of the anaerobic glycolysis (grouping them together is ok) b. allosteric controlled enzymes of the tricarboxylic acid cycle (grouping them together is ok) c. NADH d. The mitochondrial electron transport chain e. The H+ gradient across the inner mitochondrial membrane f. The ATP synthetase g. ATP h. ADP E. Write a figure legend that summarizes the mechanisms illustrated in your diagram. 250 word maximum. (9 pts) This is what I have so far, In biochemistry, allosteric regulation (or allosteric control) is the regulation of a protein by binding an effector molecule at a site other than the protein’s active site. The site to which the effector binds is termed the allosteric site. Okay, so for A, we know that the inhibitors will lower NADH until the levels become too low and need to be raised again. At this point, allosteric inhibitors will detach from the allosteric site and allow NADH production to begin again. At the point where it is too high, the inhibitors will bind and NADH will lower again. The process will repeat, causing oscillations in an attempt to maintain homeostasis. This is a classic example of negative feedback. For B, this involves both aerobic and anaerobic respiration, as glycolysis happens in both. I would assume mitochondrial NADH would show greater swings in oxidation-reduction states because more NADH is produced in the Kreb’s Cycle- which occurs in the mitochondria. To observe this, we could isolate the mitochondria and feed the reactants in and monitor the levels. For C, cyclic oscillation would be expected because the use and production of the chemicals is pretty much set. ATP and NADH will be in phase, because consumption and production occur at (~) the same time. Read more

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