Mitosis
1 Mitosis takes places in somatic cells.
2 It involves only one division.
3 It results in production of two daughter cells.
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4 Both the daughter cells show genetic Similarly with the parent cell. The chromosome number remains constant.
5 Prophase is short and simple.
6 No synisesis, synapsis, crossing over and chiasma-formation observed.
7 The chromosomes appear two threaded (univalent) exhibiting auto-orientation on
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the metaphase plate.
8 Chromosome separate into chromatids with splitting of centromere.
9 Telophase forms two groups of daughter chromosomes numerically equal to parent chromosome number.
10 Cytokinesis always follows karyokinesis forming two daughter cells.
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11 It increase cell number, helps in growth, asexual reproduction of organisms and maintains genetic stability.
12 Synaptonemal complex is not formed.
13 DNA synthesis is completed during S-phase. No delayed synthesis DNA is observed.
14 No recombination nodules are observed during mitosis.
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Meiosis
1. It occurs in reproductive cells.
2. It involves two successive divisions.
3. Four daughter cells are produced.
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4. All the daughter cells are genetically different from parent cell. The chromosome number reduce t half.
5. Prophase is of long duration, and is complicated and divided into substages.
6. Synisesis, synapsis, crossing over and chiasma formation are characteristic of prophase-I, Prophase-II is similar to mitotic prophase.
7. The homologous pair appears four threaded (bivalent) showing co-orientation in metaphase-I. But metaphase-II is similar to mitotic metaphase. anaphase-I. Homologous pairs
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8. Centromere does not split in separate. But during anaphasell it follows mitotic pattern.
9. Chromosome number reduces to half in Telophase-I, Telophase-II is similar to mitosis.
10. Sometimes cytokinesis is absent in meiosis-I. But in meiosis-II cytokinesis results in the formation of four daughter cells.
11. It restores chromosome number in organisms and brings about variation through crossing genetic over.
12. The tripartite, proteinous synaptonemal complex is formed during zygotene that disappears in diplotene of prophase-I.
13. Besides DNA synthesis at S-phase, synthesis of a small fraction of DNA (0.3%) is observed during zygotene.
14. Recombination nodules are found to be associated with pachytne chromosomes with are believe to be involved in exchange of chromosomal segments.