If tyrosine becomes a conditionally essential amino acid in the body, which of the following statements is true? a. Tyrosine should be taken in through the diet as the body is unable to produce it. b. Tyrosine is produced in excess by the body, and its intake through the diet should be limited. c. Phenylalanine is produced using tyrosine and should be supplied in adequate quantities. d. The excess absorption of phenylalanine prevents the absorption of tyrosine by the body. e. Tyrosine is not required by the body for the synthesis of other essential amino acids.

The correct answer is A. Tyrosine should be taken in through the diet as the body is unable to produce it.

Explanation:

Tyrosine is an organic chemical compound. It performs important biological tasks as an intracellular transmitter (it can be phosphorylated by protein kinases), and is also a precursor to important hormones and biologically active substances (thyroxine, triiodothyronine, adrenaline, noradrenaline and dopamine).  

It is an endogenous amino acid, which means that the human body and most animals are able to synthesize it provided that there is sufficient supply of phenylalanine, from which tyrosine differs by the presence of one hydroxyl group.  

Tyrosine is very important for the proper functioning of the thyroid and pituitary gland. Lack of this amino acid causes hypothyroidism, which can manifest itself in the form of fatigue and exhaustion. Reducing the amount of tyrosine in the body causes a deficiency of norepinephrine and dopamine, which can cause depression.

i say that the answer is 'd'