Question

It is my understanding that tertiary structure describes the three dimensional folding, so I am not sure if I am simply overthinking this or what but I am confused by this question:

The specific three-dimensional folding of a protein is ultimately determined by

	a.	the secondary structure
	b.	the primary structure
	c.	the tertiary structure
	d.	the number of alanine residues
	e.	interactions with other proteins

Answer 1

answer is primary structure

The primary structure of a protein, its amino acid sequence — drives the folding and intramolecular bonding of the linear amino acid chain, which ultimately determines the protein's unique three-dimensional shape.

Hydrogen bonding between amino groups and carboxyl groups in neighboring regions of the protein chain sometimes causes certain patterns of folding to occur. Known as alpha helices and beta sheets, these stable folding patterns make up the secondary structure of a protein.

The ensemble of formations and folds in a single linear chain of amino acids called a polypeptide that constitutes the tertiary structure of a protein