Question

Which of the following is a globular protein?
A.Collagen
B.Myoglobin or Hemoglobin
C.Myosin
D.Fibroin

Answer 1

Hint: Globular proteins are formed when the chains of polypeptides coil around to give a spherical shape. These types of proteins are usually soluble in water. So, to solve this question we need to classify proteins into different types.

Complete step by step answer:
Proteins are the macromolecules formed by amino acids. A total of 20 different amino acids exist in proteins and hundreds to thousands of these amino acids are attached to each other in long chains to form a protein. The structure of proteins is generally made up of amino acids forming peptide bonds. Now, let’s see the formation of a peptide bond.

Now, proteins are further classified as fibrous proteins and globular proteins.
Fibrous proteins- When the polypeptide chains run parallel and are held together by hydrogen and disulfide bonds, then the fiber-like structure is formed. Such proteins are insoluble in water and are known as water- soluble proteins. Some of the examples of these types of proteins are keratin, myosin, collagen and fibroin
Globular proteins- This structure is formed when the chains of polypeptide coil around to give a spherical shape. These proteins are usually soluble in water. Some of the examples of these types of proteins are insulin, albumins, myoglobin or hemoglobin.

Hence, option B is correct.

Note: In polypeptide chains, the main structure of protein relates to the amino acid sequence Moreover, the primary structure is bound together by peptide bonds that are made during the phase of protein biosynthesis. This structure is generally determined by the gene corresponding to the protein.