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In certain species of diatoms, auxospores are specialised cells produced at key stages in their life history. Auxospores typically play a role in growth processes, sexual reproduction or dormancy^[1].

Auxospores play a role in cell growth because successive mitotic cell divisions in diatoms leads to a decrease in cell size. This occurs because each daughter cell produced by cell division inherits one of the two valves that make up the silica cell wall, and then grows a smaller valve within it. Consequently, each division cycle decreases the average size of diatom cells in a population. When its size becomes too small, a dividing diatom cell produces an auxospore to expand its cell size back to that which is normal for vegetative cells^[2].

Auxospores can also play a role in sexual reproduction in diatoms, and may be formed after haploid gametes fuse to form a diploid zygote^[3].

Finally, auxospores can be formed by diatoms to act as dormant resting stages. These are used to survive periods of time that are unfavourable to growth, such as winter or while nutrients are depleted.

References

^ Hoek, C. van den, Mann, D. G. and Jahns, H. M. (1995). Algae : An introduction to phycology, Cambridge University Press, UK.
^ Assmy, P., Henjes, J., Smetacek, V. and Montresor, M. (2006). Auxospore formation by the silica-sinking, oceanic diatom Fragilariopsis kerguelensis (Bacillariophyceae). J. Phycology 42, 1002-1006.
^ Chepurnov, V.A., Mann, D.G., Sabbe, K. and Vyverman, W. (2004). Experimental studies on sexual reproduction in diatoms. International Review of Cytology 237, 91-154.

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[hoek95-1] Hoek, C. van den, Mann, D. G. and Jahns, H. M. (1995). Algae : An introduction to phycology, Cambridge University Press, UK.

[2] Assmy, P., Henjes, J., Smetacek, V. and Montresor, M. (2006). Auxospore formation by the silica-sinking, oceanic diatom Fragilariopsis kerguelensis (Bacillariophyceae). J. Phycology 42, 1002-1006.

[3] Chepurnov, V.A., Mann, D.G., Sabbe, K. and Vyverman, W. (2004). Experimental studies on sexual reproduction in diatoms. International Review of Cytology 237, 91-154.

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	In certain species of [[~~algae~~]], '''auxospores''' are specialised [[cell (biology)\|cells]] produced ~~by [[diatom]]s~~ at ~~certain~~ key stages in their life history. Auxospores typically play a role in growth processes, [[sexual reproduction]] or [[dormancy]]<ref name=hoek95>Hoek, C. van den, Mann, D. G. and Jahns, H. M. (1995). ''[http://books.google.co.uk/books?id=xuUoiFesSHMC&printsec=frontcover Algae : An introduction to phycology]'', Cambridge University Press, UK.</ref>.		In certain species of [[diatom]]s, '''auxospores''' are specialised [[cell (biology)\|cells]] produced at key stages in their life history. Auxospores typically play a role in growth processes, [[sexual reproduction]] or [[dormancy]]<ref name=hoek95>Hoek, C. van den, Mann, D. G. and Jahns, H. M. (1995). ''[http://books.google.co.uk/books?id=xuUoiFesSHMC&printsec=frontcover Algae : An introduction to phycology]'', Cambridge University Press, UK.</ref>.

	Auxospores play a role in cell growth because successive [[mitosis\|mitotic]] [[cell division]]s in diatoms leads to a decrease in cell size. This occurs because each daughter cell produced by cell division inherits one of the two valves that make up the [[silicic acid\|silica]] [[cell wall]], and then grows a smaller valve within it. Consequently, each division cycle decreases the average size of diatom cells in a population. When its size becomes too small, a dividing diatom cell produces an auxospore to expand its cell size back to that which is normal for [[vegetative reproduction\|vegetative cells]]<ref>Assmy, P., Henjes, J., Smetacek, V. and Montresor, M. (2006). [http://southampton.library.ingentaconnect.com/content/bsc/jpy/2006/00000042/00000005/art00004 Auxospore formation by the silica-sinking, oceanic diatom ''Fragilariopsis kerguelensis'' (Bacillariophyceae).] ''J. Phycology'' '''42''', 1002-1006.</ref>.		Auxospores play a role in cell growth because successive [[mitosis\|mitotic]] [[cell division]]s in diatoms leads to a decrease in cell size. This occurs because each daughter cell produced by cell division inherits one of the two valves that make up the [[silicic acid\|silica]] [[cell wall]], and then grows a smaller valve within it. Consequently, each division cycle decreases the average size of diatom cells in a population. When its size becomes too small, a dividing diatom cell produces an auxospore to expand its cell size back to that which is normal for [[vegetative reproduction\|vegetative cells]]<ref>Assmy, P., Henjes, J., Smetacek, V. and Montresor, M. (2006). [http://southampton.library.ingentaconnect.com/content/bsc/jpy/2006/00000042/00000005/art00004 Auxospore formation by the silica-sinking, oceanic diatom ''Fragilariopsis kerguelensis'' (Bacillariophyceae).] ''J. Phycology'' '''42''', 1002-1006.</ref>.