When Proteins Are Broken Down into Their Subunits, What Happens

Multiple Choice

When proteins are broken down into their subunits, what happens to the amino group removed from the amino acids that are not used to rebuild proteins or other molecules?

A) They are formed into acetyl-CoA.
B) They are converted into pyruvate.
C) They are excreted in the urine.
D) They are stored as glycogen in liver.
E) They are stored in vacuoles in muscle.