Link to Learning Click through the steps of this interactive animation to compare the meiotic process of cell division to that of mitosis: How Cells Divide. In anaphase II, the sister chromatids are separated. Meiosis and mitosis are both preceded by one round of DNA replication; however, meiosis includes two nuclear divisions.
These steps are homologous chromosome pairing, crossover exchanges, sister chromatids remaining attached during anaphase, and suppression of DNA replication in interphase. Meiosis and mitosis share obvious cellular processes and it makes sense that meiosis evolved from mitosis.
In other organisms, cytokinesis—the physical separation of the cytoplasmic components into two daughter cells—occurs without reformation of the nuclei. Cells containing two sets of chromosomes are called diploid. No, count again.
This randomness is the physical basis for the creation of the second form of genetic variation in offspring. Sex cells have one set of chromosomes; body cells have two. A partial synaptonemal complex develops only between the regions of homology.
That is correct. Marilee Ramesh and colleagues. In this case, the duplicated chromosomes only one set of them line up on the metaphase plate with divided kinetochores attached to kinetochore fibers from opposite poles.
The mechanics of meiosis II is similar to mitosis, except that each dividing cell has only one set of homologous chromosomes. Meiosis is such an extraordinarily complex series of cellular events that biologists have had trouble hypothesizing and testing how it may have evolved.
Remix published on Aug 18, by Tina B. In most plants and all animal species, it is typically diploid cells that undergo mitosis to form new diploid cells.