Pleodorina

Drawing of a colony Pleodorina

Pleodorina is a genus of algae from the class of Chlorophyceae.

Description

Pleodorina forms approximately spherical colonies of mostly 128, rare 64 or 32 cells 180-450 microns in diameter. The cells are located in the periphery in a common jelly and are not arranged in rings ( floors). The cells have a nucleus, two flagella and a drip- shaped chloroplasts with an eyespot. The design principle of the cells correspond to those of Chlamydomonas. The cells of a full-blown colony are clearly unequal in size; the front are small (somatic cells), the rear two to three times as large ( generative cells). Somatic cells have a pyrenoid, generative cells more.

Reproduction

In asexual reproduction, a generative cell forms within the jelly of the mother colony a daughter colony. Each generative cell is capable of this form of reproduction.

Sexual reproduction takes place by oogamy ( egg fertilization ). Sperm packets are formed in male colonies, an egg is produced by conversion of a generative cell in female colonies.

Types (selection)

• Pleodorina illinoisensis
• Pleodorina japonica
• Pleodorina starrii
• Pleodorina thompsonii

Dissemination

Pleodorina living planktonic in stagnant water.

Swell

• Karl -Heinz Linne von Berg, Kerstin Hoef -Emden, Birger Marin, Michael Melkonian: The Cosmos algae leader. The main freshwater algae under the microscope. Franckh Cosmos, 2006, ISBN 3-440-09719-6.