Biomolecules PYQ's (MCQ's)

By -

 Visit You tube channel for more MCQ's: https://www.youtube.com/channel/UCDI5O7VNvIby-Faq_ptLefw

Previous Year Question's

1. Lecithin, a small molecular weight organic compound found in living tissue is an example of:      (2024)

1) Amino acids     2) Phospholipids

3) Glycerides        4) Carbohydrates

Ans. 4 - Phospholipids   

Explanation: Some lipids have phosphorous and a phosphorylated organic compound in them. These are called phospholipids. Lecithin is one example.  

2. The cofactor of the enzyme carboxypeptidase is:                                                                      (2024)

1) Zinc          2) Niacin
3) Flavin       4) Haem

Ans. 1 - Zinc

Explanation: Zinc is a cofactor for the proteolytic enzyme carboxypeptidase. Coenzymes like NAD and NADP contains the vitamin niacin. Haem is the prosthetic group in peroxidase and catalase.

3. Inhibition of succinic dehydrogenase enzyme by malonate is classical example of:             (2024)

1) Co-factor inhibition               2) Feedback inhibition
3) Competitive inhibition          4) Enzyme inhibition

Ans. 3 - Competitive inhibition

Explanation: When an inhibitor closely resemble the substrate in its molecular structure and inhibits the activity of an enzyme, it is known as competitive inhibitor. Due to its close structural similarity with the substrate, the inhibitor competes with the substrate for the substrate binding site of the enzyme. Consequently the substrate cannot bind and as a result, the enzyme action declines. e.g. inhibition of succinic dehydrogenase by malonate which closely resembles the substrate succinate in structure.


  

Comments

Post a Comment

Popular posts from this blog

Molecules and their Interactions Relevant to Biology (PYQ's) (SET1)

By -
Image
Visit You tube channel for more MCQ's:  https://www.youtube.com/channel/UCDI5O7VNvIby-Faq_ptLefw Previous Year Questions (PYQ's) 1. From the following statements,                                                                                         (DEC 2016) a) Hydrogen, Deuterium and Tritium differ in the number of protons. b) Hydrogen, Deuterium and Tritium differ in the number of neutrons. c) Both Deuterium and Tritium are radioactive and decay to hydrogen and deuterium respectively. d) Tritium is radioactive and decays to helium. e) Carbon-14 decays to Nitrogen-14. f) Carbon-14 decays to Carbon-13. Pick the combination with all correct statements. A) a, b and f      B) b, d and e C) a, c and d      D) c, e and f Ans. B - b,...
Read more

Molecules and their Interactions Relevant to Biology (PYQ's) (SET2)

By -
Visit You tube channel for more MCQ's:  https://www.youtube.com/channel/UCDI5O7VNvIby-Faq_ptLefw Previous Year Questions: 1. Chitin is absent in which group ?                                                                         (Dec 2008) 1) Bacteria          2) Arthropods 3) Fungus            4) Mollusca Ans. 1 - Bacteria Explanation: Chitin is a polysaccharide found in the exoskeleton of arthropods like insects and crustaceans, as well as in the cell wall of fungi, it can also be found in the shells of some molluscs, it is not found in bacteria. Hence option 1 is correct. 2. Which of the following is a most hydrated polymer?                                  ...
Read more

Chapter 1. Heredity and Evolution

By -
Image
1.     Heredity and Evolution Introduction: Basic unit of life is cell. Controlling center of cell is nucleus. Inside nucleus there are chromosomes. Chromosomes are made up of DNA. Segment of DNA is called as gene. ✱ Heredity and Hereditary Changes: Heredity: Transfer of characters from one generation to another via genes. Johann Gregor Mendel - Father of modern genetics. Hugo de Vries - Mutation Theory (1901). Walter and Sutton - Observed paired chromosomes in cells of grasshopper. Ostwald Avery, Maclyn McCarthy and Colin MacLeod - Except viruses, all living organisms have DNA as genetic material (1944). Francois Jacob and Jack Monad - Proposed a model for process of protein synthesis. Science of heredity is useful for: Diagnosis, treatment and prevention of hereditary disorders. Production of hybrid varieties of animals and plants. In industrial processes in which microbes are used. ✱ Structure of DNA (Deoxyribo Nucleic Acid) Chromosomes are made up of DNA. Chromosomes are a...
Read more