Question

Although both pyruvate dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase use NAD as their electron acceptor, the two enzymes do not compete for the same cellular NAD pool. Why?Choose ONE answer:a. NAD+ is only used once before being degraded, so it is not regenerated for subsequent rounds.b. The NAD+ pool in the mitochondria and cytosol are separated by the mitochondrial membranec. The enzymes are found in different types of cellsd. Both enzymes use FAD as their electron acceptors.e. The pyruvate dehydrogenase reaction uses FAD as its sole electron acceptor whereas glyceraldehyde 3-phosphate dehydrogenase uses NAD+f. NAD+ remains tightly bound to each enzyme, so the NAD pools are not shared.

Answer 1

Answer:

. The NAD+ pool in the mitochondria and cytosol are separated by the mitochondrial membranece

Explanation:

The location of these 2 enzymes provided an insight to this:

.

Pyruvate dehydrogenase is located in the MATRIX of mitochondrial,

The Glyceride 3 phosphate is located in the CYSTOSOL.

These 2 locations are separated by the double intramembranes of the mitochondrial.Thus the separation cut the mitochondrial and cytosolic acess to the same Co enzyme NAD pool.

Therefore it ensured no competition between the same enzymes for the same NAD.pools.

It is important to note that: shuttle mechanisms allow the tranfer of reduced equivalents from one nicotanimide coenzymes to another.