Tbr cbt 4 q

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greenseeking

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In exercising muscles, where the oxygen concentration is low, the rate of glycolysis increases because of an increase in the cytosolic concentrations of:

A. ATP.
B. ADP.
C. NAD+.
D. glucose

Why isn't it C? Narrowed it down into C and B... Answer is B.
 
In exercising muscles, where the oxygen concentration is low, the rate of glycolysis increases because of an increase in the cytosolic concentrations of:

A. ATP.
B. ADP.
C. NAD+.
D. glucose

Why isn't it C? Narrowed it down into C and B... Answer is B.

Exercise requires ATP. Lots of ATP consumption = lots of ADP. I don't know how NADH is oxidized to NAD+, but I don't think it's due to low O2.
 
Exercising muscles have a deficit of NAD+. Pyruvate is turned into lactate under anaerobic conditions for the purpose of regenerating NAD+ so glycolysis can continue.
 
Hate to bring up an old topic but I'm a little confused on this problem as well. I thought it was C too.

I thought that was kind of the point of converting pyruvate to lactate, so you could change the NADH to NAD so that glycolysis could continue?

I understand that a lot ADP will be created but when I looking at the steps in the picture from the passage - Step 6 required NAD to be reduced to NADH and Step 7 requires ADP. Thinking sequentially, I thought it would NAD would be the answer

Can anyone help explain this for me?
 

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Hate to bring up an old topic but I'm a little confused on this problem as well. I thought it was C too.

I thought that was kind of the point of converting pyruvate to lactate, so you could change the NADH to NAD so that glycolysis could continue?

I understand that a lot ADP will be created but when I looking at the steps in the picture from the passage - Step 6 required NAD to be reduced to NADH and Step 7 requires ADP. Thinking sequentially, I thought it would NAD would be the answer

Can anyone help explain this for me?

NAD+ is neither built up or depleted, it is repetitively oxidized and then reduced again in the cycle. ADP is built up by exercising muscles (as a byproduct of ATP breakdown) and serves as a stimulus for glycolysis
 
somewhere in the bio berkeley book, it says that the energy-involving steps are usually the steps that also regulate cycles.
 
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