Learn about the Comparison between Meiosis and Mitosis.
Comparison # Meiosis:
1. In mitosis, chromosome doubling is followed by separation of daughter chromosomes, i.e., there is division of centromere in mitosis.
2. Mitosis occurs in all the cells of the body.
3. It completes in one sequence of stages, i.e., there is only series of divisional stages.
4. Prophase of mitosis is of short duration and is without sub-stages.
5. The homologous chromosomes do not pair with each other, i.e., synapsis is absent.
6. Duplication of chromosomes takes place in the early prophase.
7. Generally, no chiasma formation takes place. Thus, exchange of genetic material between the homologous chromosomes does not take place.
Metaphase:
8. Chromosomes appear two stranded.
9. The centromere of each chromosome divides into two and thus the two chromatids of the chromosome become free from each other.
Anaphase:
10. The two chromatids of each chromosomes move towards the opposite poles of spindle.
11. The daughter chromosomes appear in singlet state.
12. The chromosomes are long and thin.
Telophase:
13. The first telophase is sometimes omitted.
Significance:
14. The chromosome number in each daughter nucleus remains the same as in parent nucleus.
15. A diploid cell will produce two diploid cells by a mitosis.
Comparison # Meiosis:
1. In meiosis, there is doubling of chromosomes once which is followed by two nuclear divisions, i.e., the centromeres of chromosomes divide only once usually at the equational phase or division II.
2. It occurs in the reproductive or germ cells.
3. The whole process completes into two successive divisions.
4. The prophase I is of longer duration and completes in the five substages, viz., leptotene, zygotene, pachytene, diplotene and diakinesis.
5. In Meiosis I, the homologous chromosomes (paternal and maternal chromosomes) which are in singlet states form pairs during the zygotene stage and it appears as if the chromosome number has become reduced to half.
6. Duplication of chromosomes takes place in the pachytene substage of meiosis I.
7. Chiasma formation takes place during diplotene and diakinesis substages of prophase I. Thus, the exchange of genetic material takes place between the non-sister chromatids of homologous chromosomes.
8. Since homologous chromosomes do not separate in prophase I, the chromosome pairs appear in tetrad state, i.e., four stranded in metaphase I.
9. Centromeres of the homologous chromosomes do not divide, thus their chromatids do not become free in the metaphase I.
10. In meiosis I, the two homologous chromosomes of each bivalent separate and move towards the opposite poles of spindle during anaphase stage.
11. The separated chromosomes are two stranded but their centromeres remain still in undivided state. However, the centromere is spli into two during the Metaphase II.
12. The chromosomes are short and thick.
13. The telophase always comes after anaphase.
14. In meiosis, the chromosome number of parent is reduced to half in the daughter nucleus.
15. A diploid cell produces four haploid cells by a meiosis.