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Article: Embryogenesis and larval differentiation in sponges (1).
- Article from:
- Canadian Journal of Zoology
- Article date:
- February 1, 2006
- Author:
CopyrightCOPYRIGHT 2006 NRC Research Press. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Abstract: Having descended from the first multicellular animals on earth, sponges are a key group in which to seek innovations that form the basis of the metazoan body plan, but sponges themselves have a body plan that is extremely difficult to reconcile with that of other animals. Adult sponges lack overt anterior-posterior polarity and sensory organs, and whether they possess true tissues is even debated. Nevertheless, sexual reproduction occurs as in other metazoans, with the development of embryos through a structured series of cellular divisions and organized rearrangements of cellular material, using both mesenchymal and epithelial movements to form a multicellular ...