B. NADPH. These agents are found along the sorbitol pathway. This pathway is important in understanding the breakdown of glucose in the body. One molecule of glucose can either undergo reduction to sorbitol in a low oxygen environment or can be converted directly to fructose 6-phosphate.

A. ACTH (adrenocorticotropic hormone). ACTH secretion is diurnal and regulated by corticotropin releasing hormone. This secretion is increased during stress and highest in the morning.

D. Epinephrine is derived from Tyrosine. Tyrosine molecules are converted to dopamine which leads to production and release of norepinephrine. Norepinephrine is converted to epinephrine via methyltransferase.

C. Tryptophan is the sole precursor for the synthesis of serotonin. We acquire this amino acid through our diet only.

C. In this example of non-competitive inhibition, one would expect Vmax to decrease, Km to remain constant, and the Lineweaver-Burk plot to shift upwards. In competitive inhibition, the ligand will bind to the active site in place of the substrate. This will cause Vmax to remain constant, Km to increase, and the plot to shift to the right.

E. Vitamin C is soluble in water. To recall, “DEAK” are the four fat soluble vitamins.