Study guides & original practice
Mitosis versus meiosis practice
Distinguish the purpose of a division from the details of what separates. Mitosis generally preserves chromosome number; meiosis reduces it through two divisions following one round of DNA replication.
By ExamCat · Original study lesson · Published September 24, 2026
Understand the method
Homologous chromosomes separate in meiosis I. Sister chromatids separate in meiosis II and in mitotic anaphase. Count chromosomes by centromeres when following a diagram, and do not confuse replicated DNA content with chromosome number.
Worked example, step by step
A diploid cell has 2n = 8. Track chromosome number in the products of mitosis and meiosis.
- Before replication, the cell has eight chromosomes.
- Replication produces sister chromatids but does not by itself double the centromere-based chromosome count.
- Ordinary mitosis produces two cells with eight chromosomes each.
- Completed meiosis produces haploid products with four chromosomes each, assuming normal segregation.
A mistake to watch for
“DNA doubled” does not automatically mean “chromosome number doubled.” Specify the stage and whether you mean chromosomes, chromatids or DNA amount.
Try it yourself: three questions
Write an answer before opening the explanation. For calculations, keep your units and intermediate steps; for concepts, state the reason for your choice.
1. If 2n = 12, what is n?
Show answer and explanation
Six. A haploid set contains one chromosome from each homologous pair.
2. What separates during meiosis I?
Show answer and explanation
Homologous chromosomes. Sister chromatids normally remain together until meiosis II.
3. Are meiotic products ordinarily identical copies?
Show answer and explanation
No. Recombination and chromosome assortment can produce different combinations of genetic material. This differs from the usual purpose of mitotic copying.
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Further reading
OpenStax Biology 2e provides textbook background. The worked scenario and practice questions on this page were written independently for ExamCat.
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