The three-dimensional structure of a protein is determined by its primary, secondary, and tertiary structures. Define the primary, secondary, and tertiary structures. What are some of the common secondary structures?

Answer & explanation:

The primary structure of a protein can be defined as the main chain of the protein formed by the binding of amino acids and which shows the sequence in which they appear is called the primary structure of the protein.

The secondary structure usually results from the hydrogen bonds that occur between the hydrogen (H) of the amino group (-NH) of one amino acid and the oxygen (O) of the carbonyl (C = O) of another.

The most common secondary structures are alpha helices, which look like springs (found in the keratin in our hair) and the beta pleated sheets, like folded sheets of paper (an example is the fibroin found in a spider's web or the cocoon of a moth).

The tertiary structure is formed when the primary structures of proteins fold over themselves.

This structure is usually the result of sulfur bonds, known as disulfide bonds, but other bonds, such as those made by metal atoms, can occur.

An example of a tertiary structure protein is myoglobin, which acts as a reserve of oxygen in the muscles of mammals.