Charophyceae

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Charophyceae
CharaFragilis.jpg
Chara fragilis
Scientific classification
Domain: Eukaryota
(unranked): Archaeplastida
Kingdom: Plantae
(unranked): Viridiplantae
Division: Charophyta
(unranked): Streptophyta
Class: Charophyceae
Smith, 1938
Synonyms
  • Characeae Rabenhorst, 1863[1]

Charophyceae is a class (biology) of charophyte green algae. Some botanists include Charophyceae and chlorophyte green algae in the plant kingdom.[2] Charophyceae are a class within the Streptophyta.[3][4][5] Current consensus treats Charophyceae as a class under division Charophyta, with Chlorophyta remaining a distinct division.[6]

Many of the complex traits related to sexual reproduction, photosynthesis, and other defining characteristics of plants evolved first in Streptophytes; analysis of cpDNA (chloroplast DNA), for instance, reveals that many characteristics of plant chloroplasts evolved first in the Streptophyte genera Staurastrum and Zygnema.[2][7]#

Description[edit]

The thallus is erect with regular nodes and internodes. At each node there is a whorl of branches. The whole plant is calcified and Equisetum-like. The internodes of the main axis consist of a single elongated cell, in Chara the internodes are corticated covering the main axis. In other genera these are absent. Where there is a single row of cortical cells the cortex is referred to as diplostichous, where there are two rows of cortical cells it is termed triplostichous. The intermodal cells elongate and do not divide they be come many times longer than broad.[8]

References[edit]

  1. ^ Rabenhorst, L. (1863). Kryptogamen-flora von Sachsen, pp. xiv, 282, 'Characeae'.
  2. ^ a b Campbell, N. A. & Reece, J. B. 2005. Biology, Seventh Edition. Benjamin Cummings, San Francisco.
  3. ^ Hoek, C. van den, Mann, D. G. & Jahns, H. M. 1995. Algae: An Introduction to Phycology. Cambridge University Press, Cambridge. ISBN 0-521-30419-9
  4. ^ Streptophytina
  5. ^ McCourt, R. M., Chapman, R. L., Buchheim, M. & Mishler, B. D. “Green Plants”. Accessed 13 December 2007
  6. ^ Guiry, M.D. & Guiry, G.M. 2007. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. AlgaeBase.org; searched on 13 December 2007
  7. ^ Turmel, M., Otis, C. & Lemieux, C. 2005. The Complete Chloroplast DNA Sequences of the Charophycean Green Algae Staurastrum and Zygnema Reveal that the Chloroplast Genome Underwent Extensive Changes During the Evolution of the Zygnematales. BMC Biology 3:22
  8. ^ Smith, G.M. Cryptogamic Botany. Second Edition. 1955.p 121-130. McGraw-Hill Book Company.INC.