The pyruvate dehydrogenase is allosterically inhibited by all of the following except?
a) low adp/atp ratios
b) low amp / atp ratios
c) low nad+/ nadh ratios
d) low coa-sh/ acetyl-coa ratios
e) low acetyl coa / coa-sh ratios

The correct answer is option e) "low acetyl coa / coa-sh ratios".

Explanation:

Allosteric inhibition, also known as negative allosteric modulation, occurs when a ligand decreases one enzyme's affinity to its substrate by binding to a site different from the active site. One classic example of allosteric inhibition takes place in pyruvate dehydrogenase, an enzyme that converts pyruvate into acetyl-CoA by a process called pyruvate decarboxylation. Pyruvate dehydrogenase is inhibited by the end products of the reactions that it catalyzes to regulate its activity. Therefore, a low acetyl coa / coa-sh ratios would not inhibited pyruvate dehydrogenase, on the contrary, a high concentration of acetyl coa would inhibit its activity.

e) low acetyl-CoA/CoA-sh ratios

Explanation:

The enzyme pyruvate dehydrogenase is allosterically inhibited by a high concentration of some of the products of the reaction it catalyzes: NADH and Acetyl-CoA, and ATP (since its a enzyme involved in the cellular respiration, a metabolic process that converts organic molecules into energy/ATP).

So, if you have a low ratio of acetyl-CoA/CoA-sh  it means you have a more of CoA-sh than acetyl-CoA, therefore wouldn't allosterically inhibited the enzyme.

i think that c)gold was found there

but i am not sure

the most common energy conversion is from kinetic energy to potential energy, and then from potential energy to kinetic energy.

later on comes the heat energy, mechanical energy, and other energy conversions.

this energy conversion is so common that we can find it in our day to day lives as well.

- one of the most common energy conversions involves the changing of potential energy to kinetic energy or kinetic energy to potential energy