Zoology Optional 2021 Paper UPSC | IAS Paper 1 and Paper 2 Questions | Previous Years Papers (PYQs)

Zoology Optional UPSC IAS 2021 Paper 1

Paper 1 2021 SECTION A

1. Write notes in about 150 words each for Q. Nos. 1(a) to 1 (d) and answer Q. No. 1(e):

1(a) Canal system in sponges. (IAS 2021/10 Marks)

1(b) Nematocysts of Aurelia (IAS 2021/10 Marks)

1(c) Trochophore larva and its evolutionary significance (IAS 2021/10 Marks)

1(d) Origin of tetrapods (IAS 2021/10 Marks)

1(e) Draw a well-labelled diagram of avian brain. (IAS 2021/10 Marks)

2(a) What is metamorphosis? Describe the hormonal regulation of metamorphosis in insects. (IAS 2021/20 Marks)

2(b) What is alternation of generations? Illustrate this phenomenon with life history of Obelia. (IAS 2021/15 Marks)

2(c) Describe the structure and functions of internal ear in mammals. (IAS 2021/15 Marks)

3(a) What is hypothalamo-pituitary axis? Draw a well-labelled diagram of pituitary gland and describe the functions of its hormones. (IAS 2021/20 Marks)

3(b) Define nephridium. Describe the various types of nephridia found in Pheretima. (IAS 2021/15 Marks)

3(c) Describe the respiratory organs and mechanism of respiration in Pila. (IAS 2021/15 Marks)

4(a) Define double circulation. Give a comparative account of heart in reptiles, birds and mammals. (IAS 2021/20 Marks)

4(b) Describe habitat, habits and life history of Branchiostoma. (IAS 2021/15 Marks)

4(c) Give an illustrated account of life cycle of Leishmania. (IAS 2021/15 Marks)

Paper 1 2021 SECTION B

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

5(a) Vermiculture (IAS 2021/10 Marks)

5(b) FISH (IAS 2021/10 Marks)

5(c) Biological clock (IAS 2021/10 Marks)

5(d) Ecological succession (IAS 2021/10 Marks)

5(e) Biodiversity hotspots (IAS 2021/10 Marks)

6(a) Define correlation. Explain its types and methods of computing coefficient of correlation. (IAS 2021/20 Marks)

6(b) Write note on ecological pyramids with suitable examples. (IAS 2021/15 Marks)

6(c) What are pheromones? Discuss their role in insects. (IAS 2021/15 Marks)

7(a) What is transgenesis? Describe the methods and applications of transgenesis in animals. (IAS 2021/20 Marks)

7(b) Describe the principle and applications of polymerase chain reaction (PCR). (IAS 2021/15 Marks)

7(c) Explain the process of learning and memory in animals with suitable example. (IAS 2021/15 Marks)

8(a) Define ecosystem. Discuss the structure and functions of ecosystem. (IAS 2021/20 Marks)

8(b) What is apiculture? Describe the various methods of beekeeping and also add. a note on the uses of honey. (IAS 2021/15 Marks)

8(c) Differentiate between SEM and TEM. (IAS 2021/15 Marks)

Zoology Optional UPSC IAS 2021 Paper 2

Paper 2 2021 SECTION A

1. Write your answer in about 150 words for each of the following:

1(a) Describe the requirement of proteins for the initiation of transcription in an eukaryote. (IAS 2021/10 Marks)

1(b) What is modern concept of gene? Describe the test of allilism with suitable example. (IAS 2021/10 Marks) 

1(c) Define mimicry. Discuss the types of mimicry with suitable examples. (IAS 2021/10 Marks)

1(d) Describe the use of molecular techniques in animal taxonomy. (IAS 2021/10 Marks)

1(e) What is cladistics? Discuss the international code of biological nomenclature. (IAS 2021/10 Marks)

2(a) What is cell cycle? Draw an overview of molecular events during cell cycle. Discuss the role of protein kinases in the regulation of meiotic cell cycle. (IAS 2021/20 Marks)

2(b) Lysosomes are polymorphic, justify, Draw a diagram representing the dynamic aspect of lysosome system. Write down the functions of lysosomes. (IAS 2021/15 Marks)

2(c) Glycoproteins are asymmetrically distributed in a plasma membrane, explain. Give an overview of membrane function (IAS 2021/15 Marks)

3(a) What is chromosome mutation? Describe various types of polyploidy with suitable examples. Add a note on phenotypic effects of polyploidy. (IAS 2021/20 Marks)

3(b) What is chromosome theory of linkage? Describe the methods for determination of linkage using suitable examples. (IAS 2021/15 Marks)

3(c) What is Mendel's dihybrid cross? Discuss the mechanism of independent assortment using suitable example. (IAS 2021/15 Marks)

4(a) What is isolation? Describe the major isolating mechanisms which lead to speciation. (IAS 2021/20 Marks)

4(b) Enlist theories of origin of life. Explain the theory of biochemical evolution proposed by Oparin and Haldane. (IAS 2021/15 Marks)

4(c) What is fossil data? Discuss the chronological order of human evolution with suitable examples. (IAS 2021/15 Marks)

Paper 2 2021 SECTION B

5. Write your answer in about 150 words for each of the following:

5(a) Fatty acids regulate the nature of lipids, justify  (IAS 2021/10 Marks)

5(b) Define coenzyme. Explain the role of coenzymes in the regulation of metabolic reactions by giving suitable examples. (IAS 2021/10 Marks)

5(c) Explain the respiratory regulation of acid-base balance. (IAS 2021/10 Marks)

5(d) Describe the rapidly acting synaptic transmitters with suitable examples. (IAS 2021/10 Marks)

5(e) What is sperm capacitation? Describe the method of mammalian sperm capacitation in vitro. (IAS 2021/10 Marks)

6(a) What are peptide hormones? With the help of schematic diagram, discuss the epinephrine cascade for the glucose release from hepatocytes. (IAS 2021/20 Marks)

6(b) Cyclic AMP is a second messenger, justify. Discuss the importance of cyclic AMP in intracellular signal transduction with suitable example. (IAS 2021/15 Marks)

6(c) What is bioenergetics? Discuss the role of second law of thermodynamics in energy transduction. (IAS 2021/15 Marks)

7(a) Explain the basic stimuli causing pancreatic secretion. Discuss the role of pancreas in major food digestion. (IAS 2021/20 Marks)

7(b) Explain the transport of oxygen in blood. Discuss the factors that shift oxygen-hemoglobin dissociation curve. (IAS 2021/15 Marks)

7(c) Describe the functional anatomy of cochlea with suitable diagram. Write down the functions of organ of corti. (IAS 2021/15 Marks)

8(a) What are morphogens? Describe the cellular differentiation during morphogenesis. (IAS 2021/20 Marks)

8(b) What are gap junction proteins? Discuss the roles of connexins in cellular interaction. (IAS 2021/15 Marks)

8(c) What is primordial germ cell? With the help of suitable diagram, discuss the process. of oogenesis. (IAS 2021/15 Marks)