Question

which statement explains the primary difference between the structure of a nucleic acid and the structure of a protein?
a nitrogen bases form the backbone of a nucleic acid. peptides form the backbone of a protein.
b a nucleic acid consists of fatty acids. a protein consists of glycerol.
c nucleotides link together to form a nucleic acid. amino acids link together to form a protein.
d a nucleic acid has alternating base pairs. a protein has alternating peptides.

Explanation:

• Option A: Nitrogen bases do not form the backbone of nucleic acids. The backbone of nucleic acids is made up of sugar - phosphate groups. Peptides form the backbone of proteins.
• Option B: Nucleic acids are not made of fatty acids. Fatty acids are components of lipids. Proteins are not made of glycerol. Glycerol is a component of triglycerides (a type of lipid).
• Option C: Nucleotides link together via phosphodiester bonds to form nucleic acids. Amino acids link together via peptide bonds to form proteins. This correctly explains the structural difference.
• Option D: Nucleic acids have an alternating sugar - phosphate backbone, not base pairs. Proteins have a sequence of amino acids, not alternating peptides.

Answer:

C. Nucleotides link together to form a nucleic acid. Amino acids link together to form a protein.