8.3. Differences and similarities between mitosis and meiosis
Similarities and differences between mitosis and meiosis
Similarities between mitosis and meiosis
- Both mitosis and meiosis start from diploid cells (2n).
- At the interphase, before mitosis or meiosis, duplication of genetic material occurs.
- Achromatic spindles are made up of the same types of microtubules and their operation is similar.
- After telophase, in both cases, comes cytokinesis.
Differences between mitosis and meiosis
- The meiosis only can occur in diploid cells (or polyploid), while only haploid can roll mitosis.
- In mitosis there is a single division, while in meiosis there are two consecutive divisions, the first reductional, and the second, equivalent to a mitosis.
- In mitosis, 2 cells genetically identical to the initial cell (2n) are produced. In meiosis, 4n cells are produced, with half the genetic material of the initial cell.
- The mitosis is carried somatic cells for growth and repair of tissues in multicellular organisms. Single-celled organisms also use mitosis to reproduce asexually. Meiosis is used for the formation of gametes in sexual reproduction, with half of the genetic material so that, when uniting to form the zygote, the number of chromosomes of the individuals of the species is kept constant.
- In mitosis the number of chromosomes is not altered. In meiosis, haploid cells, n, are formed with half as many chromosomes as the parent cell.
- In the prophase I of meiosis tetrads are formed and occurs crossover.
- In the metaphase of mitosis, chromosomes line up on the equatorial plate by the centromere, which joins sister (identical) chromatids. In metaphase I of meiosis, they are alienated in the equatorial plate by the chiasms joining the recombined tetrads.
- In the anaphase of mitosis the two sister chromatids separate. In anaphase I the pairs of homologous chromosomes separate.
Comparison between mitosis and meiosis in relation to the number of chromosomes / chromatids in a human cell 2n = 46