SAT II Biology E : Protein Structure

Study concepts, example questions & explanations for SAT II Biology E

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : Dna, Rna, And Proteins

Disulfide bonds can add stability to the structure of a protein. The formation of disulfide bonds occurs in the formation of what level of protein structure?

Possible Answers:

Quaternary

Primary

Secondary

Tertiary

During translation

Correct answer:

Tertiary

Explanation:

The correct answer is "tertiary." Translation is a process performed by ribosomes to link amino acids together in a chain, and the order of the amino acids is based on a code from mRNA. The order of the amino acids in the chain is the primary structure. The secondary structure is the folding in that chain, mainly based on hydrogen bonds between parts of the chain and the surrounding water molecules. The tertiary structure is the actual three-dimensional structure of the protein. Disulfide bonds are covalent bonds between cysteine residues and are stronger than hydrogen bonds and give a stable, three-dimensional structure to what was originally just a chain of amino acids.

Learning Tools by Varsity Tutors