Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
PHYLUM: ROTIFERA “Wheel bearers”- Rotary animals Rotifera- “wheel bearers” Small- most 0.1mm-0.5mm Aquatic benthic (living at bottom) mostly free-living in fresh water, but some marine. The anterior part is modified to a ciliary organ, the corona or wheel organ. Body cavity a pseudocoelom. Cuticle- body covering Bilateral symmetry Body Plan- Pseudocoelom Pseudocoelom space between gut and mesoderm parts of body wall space filled with fluid for differentiation of systems storage of waste products used as hydrostatic skeleton Cuticle Cuticle- outer covering, over epidermis ◦ for protection against water loss or gain ◦ resistant to environmental chemicals Body Systems Systems they Do NOT have: circulatory system respiratory system true skeletal system Do have: Excretion: protonephridia Digestive: complete- mouth anus Muscular: longitudinal only- whiplike movements Nervous:ladder like with anterior ganglia Skeletal: hydrostatic skeleton: for movement Reproduction:most separate sexes, some parthenogenesis- “virgin birth”females produce embryos that grow and develop without fertilization by males Figure 15.18 Rotifers Video-rotifer feeding Phylum Rotifera (rotifers) have a corona with cilia (like Norelco shaver head) no cilia elsewhere Have biforked “foot” with cement glands for attachment complex digestive structures United streaming Video Clip http://player.discoveryeducation.com/inde x.cfm?guidAssetId=5CE0972F-C9714EFC-8A7E779D8A513032&blnFromSearch=1&prod uctcode=US