Difference # Mitosis:
1. The term ‘Mitosis’ was given by W. Flemming (1882).
2. Mitosis is one step process.
3. Mitosis always occurs in somatic and reproductive cells.
4. On completion one cell forms two daughter cells. Chromosome number of each daughter cell is the same as that of the parental cell (generally 2n). All the daughter cells are genetically uniform.
5. Each nucleus divides once after every ‘S’ phase i.e., equational.
6. The total DNA replication or duplication takes place during ‘S’ phase.
Prophase:
7. Synapsis does not take place. No crossing over happens. No chiasma is visible. No DNA is synthesised. Terminalization is invisible.
8. Chromosomes are visible 2n in number.
9. Relational coiling is clear between sister chromatids
10. In early prophase, the chromosomes are very long, subsequently due to progressive condensation become short.
11. Synaptonemal complex is underdeveloped.
12. Prophase is quite long in duration.
Metaphase:
13. Each chromosome is unpaired.
14. Each chromosome has two chromatids said as sister chromatids or daughter chromosomes.
15. Centromeres of all the chromosome he on the equatorial plate.
16. The chromosome number is 2n.
17. The two daughter chromosomes or sister chromatids of a chromosome do not show repulsion.
Anaphase:
18. The two sister chromosomes move to the different poles just after the longitudinal division of centromere.
19. Chromosome number is maintained 2n like parent cell.
20. Single nuclear division occurs within a cell.
Telophase:
21. Chromosomes completely uncoil.
Cytokinesis:
22. Cytokinesis occurs almost in all the species. It involves the formation of primary cell wall.
23. In all the species, telophase and interphase are evident.
24. Each cell forms two diploid daughter cells said as dyad.
25. Daughter cells generally differentiate as somatic or body cells.
Difference # Meiosis:
1. Farmer & Moore (1905).
2. Meiosis id a two step process.
3. Meiosis occurs in reproductive cells only i.e., anthers and ovules.
4. On completion of meiosis one cell forms four daughter cells. Chromosome number in each daughter cells is half (n) of that of the parent cell (2n). All the daughter cells are genetically dissimilar due to segregation and recombination.
5. Each nucleus after the ‘S’ phase undergoes two division i.e., (i) reductional and (ii) equational.
6. The total DNA replication does not take place during ‘S’ phase. About 0.03 percent of DNA is replicated during zygotene stage of prophase I.
Prophase I:
7. Synapsis is clear Crossing over occurs. Chiasma and terminalization is clearly visible.
8. n in number.
9. Absent.
10. Chromosomes are small from the very beginning and highly condensed.
11. Clearly developed between two homologous chromosomes.
12. Comparatively of short duration.
Metaphase I:
13. Bivalent chromosomes are clearly visible as homologous chromosomes are paired.
14. Each bivalent has four chromatids.
15. Lie on the either side of equatorial plate.
Metaphase II:
16. The chromosome number is n.
17. Repulsion between sister chromatids is evident from prophase itself.
Anaphase I:
18. The homologous chromosomes from each bivalent move to the different poles thus the chromosome number is reduced to n. Division of centromere does not take place. The division occurs between homologous chromosomes.
Anaphase II:
19. Chromosome number is maintained to n.
20. Double nuclear division occurs within a cell.
Telophase I:
21. Chromosomes do not uncoil completely.
22. In some species cytokinesis does not occur. It involves the formation of nuclear membrane.
23. In some species Telophase I and the following interphase is not found.
Telophase II:
24. Each cell forms four haploid daughter cells said as tetrad.
25. Daughter cells generally differentiate in gametes or spores or sex cells.
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