At about pH 7 in most cells, what happens to the amino R-group on an amino acid?

A) It acts as a base and gains a proton, giving it a positive charge.
B) It acts as an acid and loses a proton, giving it a negative charge.
C) It is reduced, and tends to act as an electron donor in redox reactions.
D) It remains neutral, like water, and does not have a charge.


Answer: A

Biology & Microbiology

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