- Cytomixis
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Cytomixis (originally called cytomyxis[1]) is a process of chromosome transfer that can occur during pollen formation in flowering plants. It results in pollen grains with chromosome numbers greater or less than the haploid number, possibly including some that are diploid or polyploid, and often producing some non-viable pollen grains.
During cytomixis "there is, at least in some flowers but probably not in all, an extrusion of chromatin from the nucleus of one [pollen-]mother-cell through cytoplasmic connections, into the cytoplasm of an adjacent mother-cell."[1] Cells may also fuse completely.
The phenomenon appears to have a genetic component.[2]
Diploid or polyploid pollen grains produced by cytomixis may have a significant role in evolution.[3]
See also
- Apomixis in flowering plants: various processes that occur in the gynoecium, some of which involve doubling the chromosome number.
- Parthenogenesis, the animal equivalent of apomixis.
References
- ^ a b Gates, R.R. (1911). Pollen formation in 0enothera gigas. Annals of Botany. 25: 909–940.
- ^ Omara, M.K. (1976). Cytomixis in Lolium perenne. Chromosoma. 55(3): 267–271.
- ^ Falistocco, E.; Tosti, N.; Falcinelli, M. (1995). Cytomixis in pollen mother cells of diploid Dactylis, one of the origins of 2n gametes. Journal of Heredity. 86(6): 448–453.
Categories: Plant reproduction
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