Multiple Choice Question on protein Structure and Functions:

What are proteins?

• Proteins are the high molecular weight of mixed polymer of alpha amino acids.
• Proteins are synthesized by dehydration and condensation of many different amino acids. 
• Due to the spatial structure of the peptide chain, the difference in the arrangement of amino acids, and the difference in the number of amino acids, there are many kinds of proteins. More than 20 kinds of amino acids
• The basic unit of protein is amino acid, its basic constituent elements are C, H, O, N, S and even some proteins contain metal elements.
• On the basis of structure protein are of four types: primary, secondary, tertiary, and quaternary structure.
• There are seven types of proteins: antibodies, contractile proteins, enzymes, hormonal proteins, structural proteins, storage proteins, and transport proteins.
• Proteins are present in every living organisms, many essential biological molecules such as Cell, enzymes, hormones, antibodies are made up of protein.
• The main sources of protein include meat, fish, dairy, lentils, beans etc.
• The main function of the proteins are they required for the structure, function, and regulation of the body’s tissues and organs.

MCQ on Proteins: 

1. Proteins are_______

(1) dipeptides

(2) tripeptides

(3) tetrapeptides

(4) polypeptides

Answer: 4

2. Proteins are polymers of______

(1) α-amino acids

(2) β-amino acids

(3) γ-amino acids

(4) δ-amino acids

Answer: 1

3. Which of the following factors is not responsible for the denaturation of proteins?

(1) Heat

(2) Charge

(3) pH change

(4) Organic solvents

Answer: 2

4. Peptide bond is a _________

(1) Covalent bond

(2) Ionic bond

(3) Metallic bond

(4) Hydrogen bond

Answer: 1

5. Which type of bonds stabilize the secondary structure of proteins?

(1) Covalent

(2) Hydrogen

(3) Electrostatic

(4) Peptide

Answer: 2

6. What is the average molecular weight of an amino acid residue in a protein?

(1) 120

(2) 110

(3) 130

(4) 140

Answer: 2

7. Which of the following bonds in not found in fibrous proteins?

(1) Phosphodiester

(2) Peptide

(3) Hydrogen bonds

(4) Disulphide

Answer: 1

8. Which of the following techniques is used to determine the protein structures?

(1) X-ray crystallography

(2) Kryptonics X-ray vision

(3) Magnetic resonance imaging (MRI)

(4) None of the above

Answer: 1

9. Which of the following proteins was first sequenced by Frederick Sanger?

(1) Myosin

(2) Insulin

(3) Myoglobin

(4) Haemoglobin

Answer: 2

10. Which of the following statements is true about the (primary ) 1° structure of proteins?

(1) The helical structure of the protein

(2) Subunit structure of the protein

(3) Three-dimensional structure of the protein

(4) The sequence of amino acids joined by a peptide bond

Answer: 4

11. Which of the following is not a fibrous protein?

(1) Keratin

(2) Myosin

(3) Collagen

(4) Albumin

Answer: d

12. Which of the following is not the classified form of conjugated proteins?

(1) Lipoproteins

(2) Glycoproteins

(3) Metalloproteins

(4) Complete proteins

Answer: 4

13. The structure in which all peptide chains are stretched out to full extension and laid side by side through intermolecular hydrogen bonds is called ______

(1) α-helix

(2) β-pleated sheet

(3) tertiary structure

(4) quaternary structure

Answer: 2

14. Fibrous and globular proteins are classified on the basis of ______ structure.

(1) primary

(2) secondary

(3) tertiary

(4) quaternary

Answer: 3

15. Which of the following statements is true about proteins?

(1) Proteins are polymers of starch

(2) Proteins are polymers of amino acids

(3) Proteins are polymers of peptide bonds

(4) Proteins are polymers of disulfide bridges

Answer: 2

16. Which of the following information is responsible to specify the three-dimensional shape of a protein?

(1) The protein’s peptide bond

(2) The protein’s amino acid sequence

(3) The protein’s interaction with other polypeptides

(4) The protein’s interaction with molecular chaperons

Answer: 2

15. Identify the correct statement.

(1) Peptide bond is formed by the loss of water molecule

(2) A protein is made of only one type of amino acid

(3) Dipeptides consists of different amino acids

(4) Glycylalanine is a tripeptide

Answer: 1

16. Which of the following statements is true about proteins?

(1) Proteins are made up of amino acids.

(2) Proteins are essential for the development of skin, teeth and bones.

(3) Protein is the only nutrient that can build, repair and maintain body tissues.

(4) All of the above

Answer: 4

17. During the formation of the peptide bond which of the following takes place?

(1) Hydroxyl group is lost from its carboxyl group of one amino acid and a hydrogen atom is lost from its amino group of another amino acid

(2) Hydrogen atom is lost from its carboxyl group of one amino acid and a hydroxyl group is lost from its amino group of another amino acid

(3)  Both (1) & (2) 

(4) None of these 

Answer: 1