Match List-I with List-II: List-I (a) Metacentric chromosome (b) Acrocentric chromosome (c) Sub-metacentric chromosome (d) Telocentric chromosome List-II (i) Centromere situated close to the end forming one extremely short and one long arm (ii) Centromere in the middle forming two equal arms (iii) Centromere at terminal end (iv) Centromere slightly away from the middle forming one shorter and one longer arm Choose the correct answer from the options given below:
Answer: (A) (a)-(iii); (b)-(i); (c)-(iv); (d)-(ii). Answer: (a)-(iii); (b)-(i); (c)-(iv); (d)-(ii) Solution: Chromosome types are classified by centromere position: metacentric has the centromere in the middle giving two equal arms (iii); acrocentric has it close to one end giving one very short and one long arm (i); sub-metacentric has it slightly off-centre giving one shorter and one longer arm (iv); telocentric has the centromere at the terminal end (ii).
- A.(a)-(iii); (b)-(i); (c)-(iv); (d)-(ii)✓
- B.(a)-(i); (b)-(iii); (c)-(ii); (d)-(iv)
- C.(a)-(ii); (b)-(iii); (c)-(iv); (d)-(i)
- D.(a)-(i); (b)-(ii); (c)-(iii); (d)-(iv)
Correct Answer
(A) (a)-(iii); (b)-(i); (c)-(iv); (d)-(ii)
Solution & Explanation
Answer: (a)-(iii); (b)-(i); (c)-(iv); (d)-(ii) Solution: Chromosome types are classified by centromere position: metacentric has the centromere in the middle giving two equal arms (iii); acrocentric has it close to one end giving one very short and one long arm (i); sub-metacentric has it slightly off-centre giving one shorter and one longer arm (iv); telocentric has the centromere at the terminal end (ii). NCERT establishes the centromere as the point holding the two chromatids/arms together; the four-type classification is a NEET extension of that concept. NCERT Reference: Ch 10, p.123, lines 14-15 — "two sister chromatids, which are held together" Scope note: Classification of chromosomes by centromere position (metacentric/sub-metacentric/acrocentric/telocentric) is chromosome morphology and is not part of the NCERT Ch 10 prose; included here as it appeared in the NEET paper.