Russian >>     
 
 Fauna
 Flora

Your mail 15Mb
 @boxmail.biz
 
[Registration]
Constructor
Free Hosting
Game server
Tests

  Organizations     Dictionary     Red List of Threatened Species     Photoalbum  
 Protozoa :: about protozoa :. Protozoan diversity

Protists exhibit an enormous range of body form, even though they are largely microscopic, mainly ranging in size from 10-200 ÷m. Over 60,000 species have been described although you can be sure this is only a fraction of the total number of protist life forms.

In multicellular animals and plants complexity of body form has evolved through division of labour among cells. Complexity in protists has evolved through specialisation of different parts of the cell - organelles and the cytoskeleton in particular.

The most striking differences among protozoa at the light microscope level are in the locomotory structures and the traditional classification of protozoa, found in most zoology textbooks and used within this unit, is based on these differences.

Protozoa may occur singly or in colonies (e.g. Volvox); may swim freely or be in contact with a substratum or be sedentary; may be housed in a shell (lorica) (e.g. foraminferans, clothed in scales or other adhering matter, or be naked; they may or may not be pigmented. They may be parasitic (e.g. Trypanosoma) or symbiotic living attached to or inside other organisms (e.g.Joenia), even inside their cells.

 

Back to section
 
Copyright © RIN 2003-2005.
Feedback