A cell has 46 chromosomes; after mitosis, how many chromosomes does each daughter cell have?

A cell has 46 chromosomes; after mitosis, how many chromosomes does each daughter cell have?

• A. 92
• B. 46
• C. 23
• D. 0

Answer: (B)

During mitosis, chromosome number is preserved so that each daughter cell ends up with the same set of chromosomes as the parent. Before mitosis, the cell copies its DNA, so each chromosome has two sister chromatids. Although there are 92 chromatids, they are organized as 46 chromosomes. When mitosis separates these chromatids into the two new nuclei, each daughter cell receives one copy of every chromosome, giving 46 chromosomes in each. That’s why the correct result is 46. The other numbers don’t fit: 92 would reflect counting chromatids rather than chromosomes; 23 is the haploid number seen in gametes after meiosis; 0 is not possible in a normal cell division.

During mitosis, chromosome number is preserved so that each daughter cell ends up with the same set of chromosomes as the parent. Before mitosis, the cell copies its DNA, so each chromosome has two sister chromatids. Although there are 92 chromatids, they are organized as 46 chromosomes. When mitosis separates these chromatids into the two new nuclei, each daughter cell receives one copy of every chromosome, giving 46 chromosomes in each. That’s why the correct result is 46.

The other numbers don’t fit: 92 would reflect counting chromatids rather than chromosomes; 23 is the haploid number seen in gametes after meiosis; 0 is not possible in a normal cell division.