Question

one amino acid from another. an r-group may contain carbon, hydrogen, nitrogen, or atoms. the model shows the general structure of an amino acid. amino group carboxyl group h h o h—n—c—c—oh r r-group (side chain) select the true statements. amino acids are monomers. all proteins are made from the same amino acid. each amino acid has a unique r-group. amino acids have carbon, hydrogen, oxygen, and nitrogen atoms.

Explanation:

• Statement A: Amino acids are the building blocks (monomers) of proteins, so this is true.
• Statement B: Proteins are made from different amino acids (there are about 20 common amino acids), so this is false.
• Statement C: The R - group is what differentiates one amino acid from another, so each has a unique R - group, this is true.
• Statement D: From the amino acid structure (amine group has N, H; carboxyl group has C, O, H; and R - group can have these too), amino acids contain C, H, O, N, this is true.

Answer:

A. Amino acids are monomers.
C. Each amino acid has a unique R - group.
D. Amino acids have carbon, hydrogen, oxygen, and nitrogen atoms.