A Normal Adult Is Placed on a Diet Containing Adequate

Multiple Choice

A normal adult is placed on a diet containing adequate amounts of all essential nutrients but no tyrosine. Which statement regarding this individual is true?

A) The person would be in negative nitrogen balance.
B) There would be a transient period of negative nitrogen balance followed by nitrogen equilibrium.
C) Urea excretion would increase above that in the pre-diet period because protein synthesis could not continue.
D) The person would be in nitrogen equilibrium.
E) The rate of synthesis of phenylalanine would decrease compared to that in the pre-diet period.