Answer: Gametes with both homologs or neither (n+1 and n-1).
- A One extra chromosome appearing in both resulting gametes
- B Gametes with both homologs or neither (n+1 and n-1)
- C Largely normal gametes with the correct chromosome number
- D Mainly a single chromosome remaining per resulting cell
Correct answer: B. Gametes with both homologs or neither (n+1 and n-1)
Explanation: Nondisjunction at Meiosis I: both homologs go to same cell. Results in n+1 and n-1 gametes. Leads to monosomy or trisomy.
The cell cycle: G1 (growth and preparation), S (DNA replication, chromosome number stays 2n but DNA content doubles), G2 (final checks before division), and M (mitosis itself) - together, G1+S+G2 make up interphase.
Concept context
Mitosis and meiosis: how cells divide for growth, repair, and reproduction.