Zoology Optional 2020 Paper UPSC | IAS Paper 1 and Paper 2 Questions | Previous Years Papers (PYQs)

Zoology Optional UPSC IAS 2020 Paper 1

Paper 1 2020 SECTION A

Q.1. Write notes on the following in about 150 words each: 

(a)  Gamontogamy in Monocystis (IAS 2020, 10 Marks)

(b) Skeleton in sponges (IAS 2020, 10 Marks)

(c) Describe different kinds of coral reefs on the basis of their formation. (IAS 2020, 10 Marks)

(d) Write a note on general characters of Prototheria. (IAS 2020, 10 Marks)

(e) Flight adaptations in birds. (IAS 2020, 10 Marks)

Q.2.(a) With the help of labelled diagrams, describe the mouth parts of house-fly, butter-fly and honey bee. (IAS 2020, 00 Marks)

(b) With the help of suitable diagrams, describe the different stages of life cycle of Nereis. (IAS 2020, 15 Marks)

(c) With the help of labelled diagrams, give an account of the larvae found in Asteroidea, Ophiuroidea and Holothuroidea. (IAS 2020, 15 Marks)

Q.3.(a) Describe the distribution, habits and habitat of Rhynchocephalia. Write a note on crocodilian and lacertilian characters of Sphenodon. (IAS 2020, 20 Marks)

(b) Explain origin of Amphibia and classify Amphibia up to sub class with characters and examples. (IAS 2020, 15 Marks)

(c) With the help of labelled diagrams only, explain the different larval stages in the life cycle of Fasciola hepatica (No description is required). 15

4.(a) Describe various accessory respiratory organs of fishes with examples. (IAS 2020, 20 Marks)

(b) Describe the respiratory organs and mechanism of respiration in Unio. (IAS 2020, 20 Marks)

(c) Give an account of aortic arches in reptiles, birds and mammals. (IAS 2020, 15 Marks)

Paper 1 2020 SECTION B

Q.5. Write notes on the following in about 150 words each: 

(a) Division of biosphere. (IAS 2020, 10 Marks)

(b) Give an account of biological rhythms. (IAS 2020, 10 Marks)

(c) Phosphorus biogeochemical cycle. (IAS 2020, 10 Marks)

(d) Transgenic animals. (IAS 2020, 10 Marks)

(e) TEM 10. (IAS 2020, 10 Marks)

Q.6.(a) What are the uses of Biotechnology in Forensic science? (IAS 2020, 20 Marks)

(b) Describe the uses of remote sensing in sustainable development. (IAS 2020, 15 Marks)

(c)  Explain the principle of spectrophotometer and describe its following components: (IAS 2020, 15 Marks)

(i) Radiation sources

(ii) Phototube

(iii) Prism 15

Q.7.(a) Describe the names of any four diseases of silkworm and their causal agents (scientific names), sources of infection, symptoms and management. (IAS 2020, 20 Marks)

(b) Describe the characteristics of social insects with examples. (IAS 2020, 15 Marks)

(c) Describe chromosome painting and its versatility in modern diagnostics. (IAS 2020, 15 Marks)

8.(a) Describe the differences between f-test and t-test. (IAS 2020, 20 Marks)

(b) Describe the principle and applications of gel electrophoresis. (IAS 2020, 15 Marks)

(c) Write scientific names of any three pests of stored grains and describe the nature of damage and management of Sitophilus oryzae. (IAS 2020, 15 Marks)

Zoology Optional UPSC IAS 2020 Paper 2

Paper 2 2020 SECTION A

Q.1.(a) What is Wobble hypothesis? How does it explain degeneracy in genetic code? (IAS 2020, 10 Marks)

(b) Describe the mechanism of sex determination in Drosophila. (IAS 2020, 10 Marks)

(c) Differentiate between sympatric and parapatric speciation with suitable examples. (IAS 2020, 10 Marks)

(d) Describe the origin of code for zoological nomenclature. (IAS 2020, 10 Marks)

(e) Describe the sequence specific DNA binding proteins. (IAS 2020, 10 Marks)

Q.2.(a) Draw an overview of eukaryotic cell cycle. Describe the roles of cyclins in the regulation of cell cycle. (IAS 2020, 20 Marks)

(b) What is transgenesis? Describe the methods for gene transfer in animals and its applications. (IAS 2020, 15 Marks)

(c) Define paleontology. Discuss the chronological order of elephant evolution. (IAS 2020, 15 Marks)

Q.3.(a) Define mutation. Describe the types, causes and applications of mutations. (IAS 2020, 20 Marks)

(b) What is nucleosome? Explain the functional elements of eukaryotic chromosomes. (IAS 2020, 15 Marks)

(c) What is RAPD? Give an account of the general methods for mapping human genome. (IAS 2020, 15 Marks)

Q.4.(a) What is Hardy-Weinberg equilibrium? Describe the principles, mechanism and its applications in population genetics. (IAS 2020, 20 Marks)

(b) Draw an ultrastructure of plasma membrane. Discuss the roles of lipids in the regulation of membrane fluidity. (IAS 2020, 15 Marks)

(c) Explain biodiversity. Discuss different grades and factors affecting the distribution of animal biodiversity. (IAS 2020, 15 Marks)

Paper 2 2020 SECTION B

Q.5.(a) Describe the basic structure and functions of immunoglobulins. (IAS 2020, 10 Marks)

(b) Draw a typical neuron action potential. Discuss the ionic basis for the propagation of nerve impulse. (IAS 2020, 10 Marks)

(c) Enlist the composition of saliva. Describe the mechanism of secretion of saliva. (IAS 2020, 10 Marks)

(d) Give a schematic representation of differentiation of sexual phenotypes during early embryonic development in mammals. (IAS 2020, 10 Marks)

(e) “Calcium is an initiator of cortical granules reaction.” Explain. (IAS 2020, 10 Marks)

Q.6.(a) Define oxidative phosphorylation. Describe the theories of mechanism of ATP synthesis. (IAS 2020, 20 Marks)

(b) What is the general mechanism of blood coagulation? Describe the intrinsic pathway for the initiation of blood clotting. (IAS 2020, 15 Marks)

(c) What are embryonic stem cells? Discuss the isolation, differentiation and therapeutic applications of embryonic stem cells. (IAS 2020, 15 Marks)

Q.7. (a) Enlist the sources of energy for muscle contraction. Describe the mechanism of contraction of skeletal muscle. (IAS 2020, 20 Marks)

(b) “Glycolysis is considered as metabolic hub.” Justify. (IAS 2020, 15 Marks)

(c) What is metamorphosis? Explain the role of thyroxine in the regulation of amphibian metamorphosis. (IAS 2020, 15 Marks)

Q.8. (a) Define programmed cell death. Explain the molecular mechanism and significance of apoptosis during early embryonic development. (IAS 2020, 20 Marks)

(b) What are vitamins? Describe the types and biological roles of fat-soluble vitamins. (IAS 2020, 15 Marks)

(c) Describe the process of glomerular filtration. Discuss the determinants of glomerular filtration rate in human. (IAS 2020, 15 Marks)