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In a cell when oxygen (O2) is limited, NAD+ levels decrease inhibiting the activities of several enzymes including the PDH complex. What other enzymes would be inhibited by low levels of NAD+?

During starvation when blood glucose levels are low, mobilization of fat reserves in adipose (fat) tissue ensues. Release of free fatty acids from adipose cells is a hormonally regulated process. Match the correct enzyme (Column A) with the correct signal (Column B) that regulates the release of free fatty acids.

The stoichiometry for fatty acid synthesis is as follows:

Oligomycin is an antibiotic that binds to the Fo complex of ATP synthase and inhibits the phosphorylation of ADP. Addition of oligomycin to an experimental system using intact mitochondria (mitochondria that are capable of cellular respiration if supplied with an oxidizable substrate) will inhibit ATP synthase.

You are doing an experiment to learn where carbon atoms are incorporated into the glucose molecule during gluconeogenesis. You label bicarbonate (HCO32-) with radioactive carbon (C*). Which enzyme will incorporate the labeled C*O2 into a substrate molecule? Will this labeled carbon end up in the glucose molecule?

Fava beans contain the compound, vicine, which can cause oxidative damage to cell membranes and proteins by creating reactive oxygen species (ROS) such as the superoxide radical (O2· −). What is a product of the pentose phosphate pathway that protects cell membranes and proteins from oxidative damage when an individual consumes fava beans?

Glycogen phosphorylase-a catalyzes the nucleophilic attack on the glycosidic bonds of the glycogen particle in what is known as a phosphorolysis reaction. Which bond(s) is(are) cleaved? What is the product of one cleavage reaction?

In glycolysis, the reaction sequence between dihydroxyacetone phosphate and 3-phosphoglycerate involves all of the following EXCEPT:

Crib death of infants when fasting (i.e., when sleeping and not eating – therefore a low blood glucose condition) is also known as sudden infant death syndrome (SIDS). SIDS was often blamed on lack of proper care by the parents of the child. It is now known that a significant number of SIDS cases are caused by a genetic defect in the gene that codes for fatty acyl-CoA dehydrogenase, the enzyme that catalyzes the first step in fatty acid β-oxidation (see question 34 for this reaction). If this enzyme is defective, energy from fatty acids is not available and gluconeogenesis is inhibited resulting in severe and life-threatening hypoglycemia (low blood glucose). Why the hypoglycemia?

The electron transport chain (ETC) is comprised of membrane-embedded enzymes that catalyze electron transfers. What are the MOBILE electron carriers associated with the ETC?