Question

Which statement best explains the level of organization of a protein that explains the primary squence of its amino acids?

Tertiary structure
Secondary structure
Primary structure
Quaternary structure

Answer 1

The correct option is primary structure.

Explantion

A protein is composed of polypeptide chain which are organized into different structure as explain below:

Primary structure

The primary structure of protein is composed of a single polypeptide chain in which amino acids are arranged in linear form. Only covalent bond (peptide bond) hold the structure.

Example

Insulin hormone

Secondary structure

In secondary structure a single polypeptide chain is arranged in beta pleated sheet or in helical form. hydrogen bond and covalent bond responsible for providing stability to structure.

Example

Myoglobin

Tertiary structure

In tertiary structure a single polypeptide chain is arranged in three dimension. covalent bond, hydrogen bond and disulfide linkage help in maintaning this structure.

Example

Secretory proteins.

Quaternary structure

It is composed of more than one polypeptide chain and arranged in three dimension forming a globular structure. covalent bond, hydrogen bond, disulfide linkage, hydrophobic and hydrophilic interaction help in maintaining this structure.

Example

Haemoglobin.