Haematococcus

Aplanospores of Haematococcus pluvialis

Haematococcus algae is a genus of the class of the Chlorophyceae.

Description

Haematococcus lives as unicellular with two very different forms.

Under favorable conditions, the algae lives as a green flagellate with a thick, swollen cell wall and two flagella of equal length. The cell body is elliptical to pyriform with Cytoplasmafäden which extend radially in the hyaline ( glassy ) cell wall. A gelatinous layer separates the cell body of the cell wall. The chloroplast is cup-shaped with several pyrenoids, a triangular pale eye spot and several contractile vacuoles in the cell periphery. The cells reach a length from 26 to 70 microns.

Under unfavorable conditions, a transformation of the cells into thick-walled, unbegeißelte and red-colored resting stages carried the so-called aplanospores. The red color results from a carotenoid, astaxanthin, which protects the cells from damage -tide in the DNA by means of UV radiation. Astaxanthin is mainly found in green algae.

Reproduction

In asexual reproduction occurs after the division of protoplasts to form four or eight zoospores, leaving the mother cell wall. The red aplanospores can freely translated either green zoospores or form again aplanospores.

Sexual reproduction takes place by isogamy. By repeated division of the protoplasts 16 or 32 small, spindle-shaped and flagellated gametes are formed. After gamete fusion in the formation of a thick-walled zygote.

Types (selection)

  • Haematococcus allmanii
  • Haematococcus carocellus
  • Haematococcus lacustris
  • Haematococcus pluvialis
  • Haematococcus zimbabwiensis

Dissemination

Haematococcus lives mainly in quickly drying up small fish, which are only sporadically filled by rain.

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.
  • Heinz Streble, Dieter Krauter: The Life in the Water. Microflora and microfauna of fresh water. A field guide .. Franckh Cosmos, 2006, ISBN 3-440-10807-4.
Chlorophyta Unicellular organism Eyespot apparatus
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