객관식
During which stage of meiosis does crossing over between homologous chromosomes occur?
74
views
9. Mitosis and Meiosis
Meiosis
객관식
During meiosis, what happens to the chromosome number from the original diploid germ cell to the resulting gametes?
A
It doubles, producing tetraploid cells from a diploid cell.
B
It is reduced by half, producing haploid cells from a diploid cell.
C
It varies unpredictably because chromosomes segregate randomly into daughter cells.
D
It remains the same, producing diploid cells from a diploid cell.
검증된 단계별 안내1
Step 1: Understand the starting point — a diploid germ cell contains two sets of chromosomes, one set inherited from each parent. This is represented as 2n, where n is the number of unique chromosomes.
Step 2: Recall the purpose of meiosis — it is a specialized cell division process that reduces the chromosome number by half to produce gametes (sperm or egg cells), ensuring genetic stability across generations.
Step 3: Recognize that meiosis consists of two consecutive divisions: meiosis I and meiosis II. During meiosis I, homologous chromosomes separate, reducing the chromosome number from diploid (2n) to haploid (n).
Step 4: During meiosis II, the sister chromatids separate, but the chromosome number remains haploid (n) because the chromatids are now individual chromosomes.
Step 5: Conclude that the chromosome number is reduced by half from the original diploid germ cell to the resulting haploid gametes, ensuring that when fertilization occurs, the diploid number is restored.
관련 영상
관련 실천
