Zoology Optional 2023 Paper UPSC | IFS Indian Forest Services Paper 1 and Paper 2 Questions | Previous Years Papers (PYQs)

Zoology Optional UPSC Forest Service Paper 1 2023

Paper 1 2023 SECTION A

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

(a) Protostomes vs. Deuterostomes (IFS 2023/8 Marks)

(b) Skeleton in Porifera. (IFS 2023/8 Marks)

(c) Vision in arthropods (IFS 2023/8 Marks)

(d) Scales in fishes (IFS 2023/8 Marks)

(e) Shell diversity in mollusca (IFS 2023/8 Marks)

2(a) What is sexual dimorphism? With the help of labelled diagrams, exhibit this in Ascaris, Give an account of the life history of Ascaris (IFS 2023/15 Marks)

2(b) Give an account of locomotor organelles in Protozoa. Discuss various modes of locomotion in this unicellular group. (IFS 2023/15 Marks)

2(c) What is coelom? Describe different types of coelom with the help of suitable diagrama. Draw a linear diagram to show the evolutionary relationship among different phyla based on their coelom. (IFS 2023/10 Marks)

3(a) “Class Reptilia is divided into five subclasses on the basis of certain openings through the skull.” Substantiate this statement with the help of five well-labelled diagrams and examples. (IFS 2023/15 Marks)

3(b) Give an elaborate account of dentition in mammals. (IFS 2023/15 Marks)

3(c) Write an essay on 'migration in birds'. (IFS 2023/10 Marks)

4(a) Give a comparative account of heart in vertebrates with the help of diagrams only (no description in required). (IFS 2023/15 Marks)

4(b) Give an account of systemic position, habit, habitat and external morphology of Herdmania. Also discuss the affinities of Herdmania. (IFS 2023/15 Marks)

4(c) Define neoteny and paedogenesis. Give an account of paedogenesis in Amphibia. (IFS 2023/10 Marks)

Paper 1 2023 SECTION B

5. Write a brief account on each of the following:

5(a) Ozone layer and its importance (IFS 2023/8 Marks)

5(b) AIDS (IFS 2023/8 Marks)

5(c) Student's t-test (IFS 2023/8 Marks)

5(d) Conditioning behaviour (IFS 2023/8 Marks)

5(e) Social behaviour in honeybees (IFS 2023/8 Marks)

6(a) Define biological rhythm. Write an account on circadian, tidal and seasonal rhythms. (IFS 2023/15 Marks)

6(b) What are biogeochemical cycles? Describe carbon cycle with a flow diagram. (IFS 2023/15 Marks)

6(c) Describe the principle, working mechanism and applications of Geiger Muller counter. (IFS 2023/10 Marks)

7(a) Write about the causative organism, pathogenecity and control measures of tuberculosis. (IFS 2023/15 Marks)

7(b) Define pollution. Explain the sources, impacts and preventive measures of water pollution. (IFS 2023/15 Marks)

7(c) Discuss about the nature of damage caused by and life cycle of the rice pest. Comment on its control measures. (IFS 2023/10 Marks)

8(a) What is population dynamics and what are its controlling factors? State how population size and density are calculated. Write a note on the importance of population dynamics. (IFS 2023/15 Marks)

8(b) What is aquaculture and its importance? Mention different phyla/groups and their candidate species used in aquaculture. Describe any two major aquaculture practices carried out in India. (IFS 2023/15 Marks)

8(c) What are two types of variables? Explain regression analysis in this context along with biological examples. (IFS 2023/10 Marks)

Zoology Optional UPSC Forest Service Paper 2 2023

Paper 2 2023 SECTION A

Q1. (a) Illustrate the mechanism of initiation of DNA replication and formation of primosome in prokaryotes. (IFS 2023, 8 Marks)

(b) Diagrammatically compare paracentric and pericentric inversions. (IFS 2023, 8 Marks)

(c) Distinguish between sympatric and allopatric speciation. (IFS 2023, 8 Marks)

(d) Explain the inheritance pattern of an autosomal recessive congenital disease showing a three-generation pedigree. (IFS 2023, 8 Marks)

(e) Discuss the significance of cladistics in the field of taxonomy. (IFS 2023, 8 Marks)

Q2. (a) Explain the use of minisatellite DNA in the process of DNA fingerprinting. (IFS 2023, 15 Marks)

(b) Discuss the isolating mechanisms that prevent interspecific crosses. (IFS 2023, 15 Marks)

(c) Describe the composition of prokaryotic ribosomes and illustrate sequential assemblies of 30S and 50S subunits during the formation of translation initiation complex. (IFS 2023, 10 Marks)

Q3. (a) Diagrammatically describe prophase stages and differentiate between anaphase I and II of meiotic cell division. (IFS 2023, 15 Marks)

(b) Describe the factors which are known to affect the Hardy-Weinberg equilibrium. (IFS 2023, 15 Marks)

(c) Explain the genic balance theory of sex determination in Drosophila. (IFS 2023, 10 Marks)

Q4. (a) Illustrate fluid mosaic model of plasma membrane and explain the mechanism of active transport through the membrane. (IFS 2023, 15 Marks)

(b) Distinguish between founder effect and bottleneck effect. How do these forces affect gene frequency of a large population? (IFS 2023, 10 Marks)

(c) Describe the role of multiple alleles in the inheritance of ABO blood group system in humans. (IFS 2023, 15 Marks)

Paper 2 2023 SECTION B

Q5. (a) Explain the physiological role of cholesterol. (IFS 2023, 8 Marks)

(b) Compare the mechanism of osmoregulation in terrestrial and marine mammals with examples. (IFS 2023, 8 Marks)

(c) Describe the role of G protein-coupled receptors in the action of steroid hormone. (IFS 2023, 8 Marks)

(d) Justify the statement with examples “Coenzymes function as second substrate of concerned enzyme”. (IFS 2023, 8 Marks)

(e) Discuss paedogenesis and neoteny with examples. (IFS 2023, 8 Marks)

Q6. (a) Draw the structure of F0F1-ATP synthase and explain the chemiosmotic concept of oxidative phosphorylation. (IFS 2023, 15 Marks)

(b) Illustrate actin myosin sliding mechanism of muscle contraction and relaxation. (IFS 2023, 15 Marks)

(c) Describe different types of placenta in eutherian mammals. (IFS 2023, 10 Marks)

Q7. (a) Discuss the process of teratogenesis in animals. (IFS 2023, 15 Marks)

(b) Describe the structure of IgG and the process of generation of antibody secreting cells. (IFS 2023, 15 Marks)

(c) Explain the counter current mechanism operating at vasa recta and its role in urine formation. (IFS 2023, 10 Marks)

Q8. (a) Describe hormonal regulation of menstrual cycle. (IFS 2023, 15 Marks)

(b) Explain the principle and protocol of in vitro fertilization in humans. (IFS 2023, 15 Marks)

(c) Describe alpha helix and tertiary structure of protein. (IFS 2023, 10 Marks)