Zoospore

A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some algae, bacteria and fungi to propagate themselves.

Flagella

There are two types of flagellated zoospores, tinsel or "decorated", and whiplash.

Tinsellated flagella have lateral filaments perpendicular to the main axis which allow for more surface area, and disturbance of the medium, giving it the property of a rudder, that is, the purpose of being used for steering.

• Whiplash flagella are straight, to power the zoospore through its medium. There is also the 'default' zoospore, which only has the propelling, 'whiplash' flagella.

• Both tinsel and whiplash flagella beat in a sinusoidal wave pattern, but when both are present, the tinsel will beat in the opposite direction of the whiplash, to give 2 axes of control of motility.

• There can be many combinations for location of the flagella, such as posterior tinsel; posterior whiplash, anterior tinsel; and anterior whiplash.

Oomycetes and heterokont algae produce distinct bi-flagellated zoospores:

The phyla Chytridiomycota (Kingdom Fungi), Oomycota (Kingdom Chromista), and Hyphochytridiomycota within (Kingdom Chromista), produce zoospores with flagella in the same order as described above (e.g. Hyphochytridiomycota produces anterior whiplash and none else). These phyla number 1000+, 580 and 16 species respectively.

Zoosporangium

A zoosporangium is the sexual structure in which the zoospores develop in a plant, fungi, or protists (such as the oomycota)

See also

• Gametangium
• Flagellum
• Fern
• Angiosperm
• Chytridiomycota

References

• C.J. Alexopolous, Charles W. Mims, M. Blackwell et al., Introductory Mycology, 4th ed. (John Wiley and Sons, Hoboken NJ, 2004) ISBN 0-471-52229-5