What is the difference in chromosome number between somatic (body) cells and gametes in humans and other diploid animals?
Answer and explanation
Correct answer: B. Somatic cells are diploid (2n) with two copies of each chromosome; gametes are haploid (n) with one copy
- Step 1: Somatic cells have two sets of chromosomes (diploid, 2n = 46 in humans), one from each parent. Step 2. Meiosis halves the chromosome count to form haploid gametes (n = 23 in humans). Answer: Somatic cells are diploid (2n) with two copies of each chromosome; gametes are haploid (n) with one copy. Why not the others: Fertilisation restores the diploid number (n + n = 2n).
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