User:Pooja srivastava/E-Museum/Porifera

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Characterstics of Porifera

  • They are generally called sponges.
  • They are sessile,sedentary and marine.
  • Body is cylindrical ,asymmetrical or radial symmetry.
  • Sponge body consists of an outer layer ectoderm ,middle layer mesenchyme and an inner layer endoderm.
  • Body also contains numerous pores called ostia through which water enters in the body.
  • The internal body space is either hollow or contains numerous canals lined with choanocytes(fllagelated cells).
  • Body also contains one or more openings called oscula by which water passes out.
  • They feed on minute organisms and small organic particles ingested by choanocytes.
  • Respiration takes place by intake of oxygen from water current.
  • The skeletal system of soponges is made up of spongin fibers and calcareous spicules.

Some common examples of Porifera