Biology CLEP Prep Practice Exam

What is the primary structure of protein?

1. Amino acid sequence

2. Hydrogen bonds

3. Disulfide bridges

4. Secondary structure

The correct answer is: Amino acid sequence

The primary structure of a protein refers to its basic sequence of amino acids joined together in a specific order. This sequence is determined by the genetic information of the organism. Hydrogen bonds and disulfide bridges are types of chemical bonds that contribute to the secondary and tertiary structures of a protein, but they are not the primary structure. Therefore, options B and C are incorrect. Secondary structure refers to the local folding patterns created by hydrogen bonding between amino acids, whereas primary structure is the specific sequence of amino acids themselves. Option D is also incorrect, as it is a term referring to a specific level of protein structure, rather than the overall primary structure. Therefore, the correct answer is A amino acid sequence.