Zoology Optional 2021 Paper UPSC | IFS Indian Forest Services Paper 1 and Paper 2 Questions | Previous Years Papers (PYQs)

Zoology Optional UPSC Forest Service Paper 1 2021

Paper 1 2021 SECTION A

1. Write a brief account about each of the following:

1(a) Nutrition and Osmoregulation in Euglena (IFS 2021/8 Marks)

1(b) Torsion in Gastropoda (IFS 2021/8 Marks)

1(c) Ambulacral system in Asterias (IFS 2021/8 Marks)

1(d) Archaeopteryx (IFS 2021/8 Marks)

1(e) Feeding mechanism of Branchiostoma (IFS 2021/8 Marks)

2(a) Describe morphological structures of Peripatus and discuss its affinities. (IFS 2021/15 Marks)

2(b) What is polymorphism? Explain different polymorphie forms in Coelenterates. (IFS 2021/15 Marks)

2(c) Describe the life history of Taenia solium and its parasitic adaptation. (IFS 2021/10 Marks)

3(a) Give a comparative account of the aortic arches in Vertebraten. (IFS 2021/15 Marks)

3(b) Describe the larval forms of Crustacea with suitable diagrams. (IFS 2021/15 Marks)

3(c) Describe the salient features of Prototheria. Explain how it is different. from Metatheria with example. (IFS 2021/10 Marks)

4(a) Describe different patterns of fish migration and write about its significance. (IFS 2021/15 Marks)

4(b) Give an account of chemical nature and function of Neurohypophyseal hormones in mammals. (IFS 2021/15 Marks)

4(c) Describe the parental care in Amphibians with suitable examples. (IFS 2021/10 Marks)

Paper 1 2021 SECTION B

5. Differentiate between the following:

5(a) Indian major carps and Exotic carps (IFS 2021/8 Marks)

5(b) Mean and Mode (IFS 2021/8 Marks)

5(c) Natality and Mortality (IFS 2021/8 Marks)

5(d) Navigation and Orientation behaviour in birds (IFS 2021/8 Marks)

5(e) Hormones and Pheromones (IFS 2021/8 Marks)

6(a) Write an account of the mission "Project Tiger" and mention the conservation strategies. (IFS 2021/15 Marks)

6(b) What is the objective of courtship behaviour? Describe courtship in Drosophila and three-spined stickleback. (IFS 2021/15 Marks)

6(c) What is phosphorus cycle? Describe the importance of phosphorus cycle as a component of Biogeochemical cycle. (IFS 2021/10 Marks)

7(a) What are the different criteria for the selection of candidate species for aquaculture? (IFS 2021/15 Marks)

7(b) What is the working principle of Transmission Electron Microscope (TEM)? Describe its application with suitable diagram. (IFS 2021/15 Marks)

7(c) What is lac? Describe in detail about the lac culture. (IFS 2021/10 Marks)

8(a) What are the common malaria causing species? Write an account of life cycle of malarial parasite and its pathogenicity in man. (IFS 2021/15 Marks)

8(b) What are independent and dependent variables? What is coefficient of correlation and how is it calculated? Illustrate with formula and range of values (r). (IFS 2021/15 Marks)

8(c) Write an account of Tiger Prawn culture with emphasis on seed resources and transportation. (IFS 2021/10 Marks)

Zoology Optional UPSC Forest Service Paper 2 2021

Paper 2 2021 SECTION A

Q1. (a) Briefly explain the contributions of George Gamow, Har Gobind Khorana, Marshall Nirenberg and Severo Ochoa in deciphering the genetic code. (IFS 2021, 8 Marks)

(b) How do proteins move through the Golgi apparatus? Explain. (IFS 2021, 8 Marks)

(c) Explain synonymy and homonymy in context of the International Code of Zoological Nomenclature. (IFS 2021, 8 Marks)

(d) Briefly discuss the role of geographical and reproductive isolations in speciation. (IFS 2021, 8 Marks)

(e) Describe different types of intercellular junctions in animal cells. (IFS 2021, 8 Marks)

Q2. (a) Explain molecular mechanism of chromosome movements in eukaryotes. (IFS 2021, 15 Marks)

(b) What is an Operon? Explain how a polycistronic structural gene is regulated by a common promoter and a combination of regulatory genes in a lac-operon. (IFS 2021, 15 Marks)

(c) Give an account of ancestry of Miocene and Pliocene proboscideans. (IFS 2021, 10 Marks)

Q3. (a) Define Linkage. Give an illustrated account of complete, incomplete and sex linkages. (IFS 2021, 15 Marks)

(b)  How does continental drift theory explain the discontinuous and restricted distribution of organisms ? (IFS 2021, 15 Marks)

(c) Explain the phenomenon of endocytosis in organisms with suitable examples. (IFS 2021, 10 Marks)

Q4. (a) Describe the principle, procedure and applications of DNA fingerprinting. (IFS 2021, 15 Marks)

(b) Define Mimicry. Enlist its causes. Explain different types of mimicry with suitable examples. (IFS 2021, 15 Marks)

(c) Give the structure and functions of nuclear envelope. (IFS 2021, 10 Marks)

Paper 2 2021 SECTION B

Q5. (a) Explain quaternary structure of haemoglobin. (IFS 2021, 8 Marks)

(b) What is Bohr’s effect? How does it promote gaseous exchange in the lungs and the tissues? (IFS 2021, 8 Marks)

(c) What are oligosaccharides? Give structural formulae and functions of biologically important maltose, sucrose and lactose. (IFS 2021, 8 Marks)

(d) Explain morphogenetic movements in gastrulation of frog. (IFS 2021, 8 Marks)

(e) Briefly write about hormonal control of digestive secretions in humans. (IFS 2021, 8 Marks)

Q6. (a) Describe structural differences among glycogen, starch and cellulose and elaborate their functions. (IFS 2021, 15 Marks)

(b) Explain countercurrent mechanism of urine concentration in the kidneys of higher vertebrates. (IFS 2021, 15 Marks)

(c) What is invasive placenta? Discuss its types, causes and risk factors. (IFS 2021, 10 Marks)

Q7. (a) Give schematic representation of electron transport chain. Describe the energy coupling mechanism in oxidative phosphorylation using chemiosmotic model. (IFS 2021, 15 Marks)

(b) Enumerate different blood coagulation factors. Explain their role in the process of blood coagulation. (IFS 2021, 15 Marks)

(c) Classify Vitamins. Discuss deficiency symptoms of fat-soluble vitamins. (IFS 2021, 10 Marks)

Q8. (a) Why do cells die? Discuss apoptosis, necrosis and autophagy. Add a note on “cell death proteins”. (IFS 2021, 15 Marks)

(b) Explain hormonal regulation of menstrual cycle in women. (IFS 2021, 15 Marks)

(c) Describe the structure and functions of neutral fats. (IFS 2021, 10 Marks)