Which of the following constitutes the primary structure of a protein?

A. The folding of a polypeptide chain

B. The linear sequence of amino acids in a polypeptide chair

C. The polypeptide chains stacked on top of each other

D. A pleated sheet

E. Several polypeptide subunits

Answer: B. The linear sequence of amino acids in a polypeptide chain.

Explanation: Protein structure is the three dimensional arrangement of amino acid molecules in polypeptide chain.

Protein has four types of structure -

1-Primary structure

2-secondary structure

3 - Tertiary structure

4 - Quaternary structure

Primary structure of protein is the simplest form of protein where amino acids are arranged in linear way. One end of polypeptide chain is Called C-terminal (Carboxyl group) and other is called N terminal (amino group). Peptide bods play important role in establishing primary structure of protein.

B. This is because this is the most simple structure of a protein