Spirogyra

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This article is about the type of alga. For the jazz band, see Spyro Gyra. For the folk band, see Spirogyra (band).

Spirogyra

Scientific classification

Kingdom:	Protista
Division:	Charophyta
Phylum:	Chlorophyta
Order:	Zygnematales
Family:	Zygnemataceae
Genus:	Spirogyra Link in C. G. Nees

Spirogyra is a genus of filamentous green alga of the order Zygnematales. It is commonly found in freshwater areas. Spirogyra measures to around 10 to 100μm in width and may stretch centimeters long. Spirogyra is a photosynthetic, eukaryotic cell. Spirals of chloroplast surround the vacuole, within which the nucleus is supported by cytoplasmic strands.

[edit] Reproduction

Single spirogyra cell

Spirogyra can reproduce both asexually and sexually. In asexual reproduction, spirogyra simply undergo mitosis to form new filaments.

Prior to sexual reproduction, spirogyra grow tube-like extensions that they use to connect to one another. These tubes connect to specific filaments of the two spirogyra. Once connected, on filament will send its DNA (The "male filament") to the filament on the other spirogyra (the "female filament"). The DNA already present in the filament and the DNA sent to the filament fuse and form a zygote/zygospore. Shortly after the zygote forms, the filaments undergo meiosis, making them diploid again.

[edit] References

John, D.M., Whitton, B.A. and Brook, A.J. (editors) 2002. The Freshwater Algal Flora of the British Isles. Cambridge University Press, Cambridge. ISBN 0 521 770513.