Compare and contrast how cells metabolize pyruvate when oxygen is present and when it isn't.

Plants have alternate ways of getting respiratory substrates to the point of triose-phosphate of glycolysis.  After that, plants have alternative steps during the carbon oxidation phase of glycolysis that affect whether or not ATP is synthesized during glycolysis.  What are these various alternatives before and after triose-phosphate?  Why are they used?  How do they affect the ATP use and yield from glycolysis?

Concerning the use of pyruvate when ratio of NADH/NAD+ is low, what is the fate of the carbon labeled in pyruvate when metabolized under these conditions? a) Production of glucose b) Oxidation to CO2 via the TCA cycle c) Conversion to pyruvate to generate oxaloacetate to move electrons to the cytosol via the malate shuttle d) Pyruvate is never metabolized by the cell, instead pyruvate is converted to lactate and solely exported for the Cori cycle and dependent on the liver to recycle the carbon skeleton

Give specifics as to what happens to pyruvate in both fermentation pathways? What are all the products of both pathways?

What is the amount of ATP yield per one glucose molecule? Is this amount always achieved? If not explain what happens to a cell’s essential metabolites when the requirement for biosynthesis is greater than the cells energy requirement? When the biosynthesis requirement is less than its energy requirement?

Why are relatively modest quantities of NAD+ needed in comparison to the vast quantity of carbohydrate fermented?

For Pyruvate Decarboxylation (Link Reaction), what are steps of cellular respiration for both aerobic (oxygen present) and anaerobic (without oxygen) respiration.  what are the Inputs and Outputs: Clearly indicate the key substrates, intermediates, and products at each stage. Location: Show where this stage of cellular respiration occurs within the cell (e.g., cytoplasm, mitochondria). Energy Production: Highlight the ATP and NADH production at this stage. Oxygen: Show where oxygen is used in the process (e.g., ETC) and where carbon dioxide is produced. Electron Carriers: Indicate the role of electron carriers such as NAD+ and FAD in transferring eleDiagrams: Use diagrams or icons to represent the structures and molecules involved, such as the mitochondria, glucose, ATP, and oxygen. Key Information like important facts or formulas relevant to cellular respiration, like the chemical equations for each stage.

What is the purpose of respiration?  What are the inputs, products, and energy required or gained? How does it differ from fermentation? in other words, how do Glycolysis, Pyruvate dehydrogenase, Kreb cycle, and electron transport chain work and connect to the production of ATP by chemiosmosis? compare that to fermentation.

Consider the net summary equation for glycolysis. Suppose 13 molecules of glucose enter glycolysis. Calculate the number of molecules produced or used (a-d) upon completion of glycolysis utilizing all 13 glucose molecules. (a) # P; used (b) # pyruvates produced (c) # NADH produced (d) #ADP used.

List the following steps of cellular respiration in order  - glycolysis-energy investment phase -pyruvate enters mitochondria  -TCA cycle  -glycoysis-energy payoff phase  -formation of acetly-CoA -electron transport chain