Bryopsidales

From Wikipedia, the free encyclopedia
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

Bryopsidales
Dead man's fingers (Codium fragile)
Scientific classification Edit this classification
(unranked): Viridiplantae
Division: Chlorophyta
Class: Ulvophyceae
Order: Bryopsidales
J.H. Schaffner
Families[1]
Synonyms
  • Caulerpales

Bryopsidales is an order of green algae, in the class Ulvophyceae.[1]

Characteristics

The thallus is filamentous and much branched and may be packed into a mass. It is coenocytic, having multi-nucleate cells consisting of cytoplasm contained within a cylindrical cell wall. There are no septae and the many discoid chloroplasts, nuclei and other organelles are free to move through the organism. The whole organism may consist of a single cell and in the genus Caulerpa this may be several metres across. In the genus Halimeda, whole seabed meadows may consist of an individual, single-celled organism connected by filamentous threads running through the substrate.[2]

Reproduction

Propagation is normally vegetative from small fragments which grow into new individuals. Under certain conditions sexual reproduction occurs in a process called holocarpy. Almost all of the cytoplasm in the thallus is converted into biflagellate gametes, which are discharged into the sea through papillae. After fertilisation, the zygote becomes a protonema and this in turn develops into a new thallus.[2][3]

References

  1. ^ a b Guiry, M.D. & Guiry, G.M. (2007). "Order: Bryopsidales taxonomy browser". AlgaeBase version 4.2 World-wide electronic publication, National University of Ireland, Galway. Retrieved 2007-09-23.
  2. ^ a b Day, Robert (1996). "The Cell Biology of the Bryopsidales". Seascope. 13.
  3. ^ Overview of the Genus Caulerpa Archived 2011-09-28 at the Wayback Machine Proceedings of the International Caulerpa taxifolia Conference, 2002.