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(Download) CS (MAIN) EXAM : 2024 ZOOLOGY (Paper 2)

Exam Name: CS (MAIN) EXAM : 2024 Zoology
Paper : 2
Year : 2024
Marks: 250
Time Allowed : Three Hours

खण्ड -A / SECTION — A

1. Write on the following in about 150 words each : 10×5 = 50

(a) Polytene chromosome
(b) Difference between male heterogamety and female heterogamety with examples
(c) Types of chromosomal aberrations
(d) Geographic versus reproductive isolation
(e) Main types of molecular mutations and their effect on phenotype

2. (a) Give an account of ultrastructure of rough and smooth endoplasmic reticulum. Also discuss the role of endoplasmic reticulum in cell secretion.
(b) Distinguish between heterochromatin and euchromatin in their structure and function with examples.
(c) What are signal molecules? How do defects in signalling pathway cause pathological changes?

3. (a) What is sex-determination? Give an account of genic balance theory of sex-determination in Drosophila with examples from abnormal karyotypes.
(b) What is DNA replication? Describe the process of DNA replication in prokaryotes.
(c) Discuss gene regulation mechanisms in E. coli.

4. (a) Describe the stages of human evolution and mention the major hominid forms giving their time of origin.
(b) What is Hardy-Weinberg law? How is gene frequency changed by mutation and genetic drift in populations?
(c) What is the difference between systematics and taxonomy? Differentiate between classical and molecular taxonomy with the tools used.

खण्ड - B / SECTION — B

5. Write on the following in about 150 words each : 10 × 5 = 50

(a) Functions of immunoglobulins
(b) ABO system of blood groups and its basis, and erythroblastosis foetalis
(c) Olfactory pathways and physiology of olfaction
(d) (i) Gastrulation in frog
(ii) Biogenetic law
(e) (i) Stem cells
(ii) Types of placenta among mammals

6. (a) Explain the structure of nephron and its role in urine formation. Add a note on hormonal regulation of urine formation.
(b) Classify hormones and write down the process of steroid hormone biosynthesis.
(c) What do you mean by teratogenesis? Explain the genetic and induced teratogenesis.

7. (a) Describe the process of spermatogenesis. Add a note on the role of Golgi bodies in the formation of acrosome.
(b) Why are vitamins also called coenzymes? Justify.
(c) Explain the mechanism of contraction in skeletal muscle. What do you mean by Rheobase and Chronaxie?

8. (a) Write about the role of liver and pancreas in digestion. Add a note on neural and hormonal regulation of their secretions.
(b) Discuss the role of oxidative phosphorylation in cellular and tissue metabolism.
(c) Describe the organogenesis of eye.