CSS past paper

CSS Zoology Past Paper 2026

CSS Zoology 2026 carries 100 marks over 3 hours. It has 7 questions.

Years

How to attempt: Attempt ONLY FOUR questions from PART-II. ALL questions carry EQUAL marks.

Question 1 (Part I) is the paper's MCQs, which are not reproduced here.

Q. 2
Discuss transcription and translation in eukaryotic cells and explain how they represent the central dogma of molecular biology.
(20)
Q. 3
Elaborate homeostasis in animals with emphasis on kidney function and osmoregulatory mechanisms.
(20)
Q. 4
Describe the major classes of biomolecules and discuss their role in maintaining structural and functional integrity of animal cells. Also describe which one of these biomolecules is most important in your opinion.
(20)
Q. 5
What is metamerism in Annelids? Explain its evolutionary and ecological implications.
(20)
Q. 6
Discuss major characteristics of reptiles and explain adaptations that enabled them to become successful terrestrial vertebrates.
(20)
Q. 7
Discuss hormonal coordination in vertebrates, detailing hormone types and mechanisms of hormone action.
(20)
Q. 8
Write short notes on any TWO of the following: (10 each)
(20)
- (a)
  Amphibians
  (10)
- (b)
  Smog – past, present and challenges
  (10)
- (c)
  Parasitic Adaptations in Platyhelminthes
  (10)

Part-II is to be attempted on the separate Answer Book.
Attempt ONLY FOUR questions from PART-II. ALL questions carry EQUAL marks.
All the parts (if any) of each Question must be attempted at one place instead of at different places.
Write Q. No. in the Answer Book in accordance with Q. No. in the Q.Paper.
No Page/Space be left blank between the answers. All the blank pages of Answer Book must be crossed.
Extra attempt of any question or any part of the question will not be considered.