1 / 96

Invertebrates

Invertebrates. Chapter 33. Most animals - invertebrates - do not have backbone. http://www.edsci-affiliates.com/images/invertebrates_divider.jpg. 1 Phylum Porifera. Sponges - lack nerves and muscles; sessile (non-motile). Most marine, live in water.

lela
Télécharger la présentation

Invertebrates

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Invertebrates Chapter 33

  2. Most animals - invertebrates - do not have backbone.

  3. http://www.edsci-affiliates.com/images/invertebrates_divider.jpghttp://www.edsci-affiliates.com/images/invertebrates_divider.jpg

  4. 1Phylum Porifera • Sponges - lack nerves and muscles; sessile (non-motile). • Most marine, live in water. • Most hermaphrodites - each individual produces sperm and eggs. • Can regenerate lost parts.

  5. http://www.gcb.vic.gov.au/gallery/SEA%20SPONGE,%20PORIFERA.jpghttp://www.gcb.vic.gov.au/gallery/SEA%20SPONGE,%20PORIFERA.jpg

  6. Sponges perforated with holes so water can flow through them (suspension-feeding) • Water drawn through pores into central cavity (spongocoel) and flows out through larger opening (osculum)

  7. 2Phylum Cnidaria • 1st organisms to have true tissues. • Basic body plan - sac with central digestive compartment (gastrovascular cavity) • Jellyfish, corals, sea anemones, and hydras. • Have nerve nets - very primitive nervous systems that move towards stimuli.

  8. 2 body plans in cnidarians. • 1Polyp stage - sessile; some live whole life this way. • 2Medusa stage - cnidarian can swim freely. • Can move through both stages during lifetime.

  9. http://library.thinkquest.org/26153/marine/sketch/613.jpg

  10. Cnidarians have nematocysts - stinging cells. • Phylum Cnidaria divided into 3 major classes: Hydrozoa (hydra), Scyphozoa (true jellyfish), and Anthozoa (sea anemones). • Cnidarians - carnivores - use tentacles to push food into gastrovascular cavity.

  11. 3Phylum Ctenophora • Comb jellies named for fused cilia. • Resemble medusa stage of cnidarians. • No stinging cells present.

  12. 4Phylum Platyhelminthes • Flatworms, both parasitic and non-parasitic. • Flatworms have mesoderm - middle layer of tissues - makes them bilateral.

  13. http://www.waterworxbali.com/Images/Photos/Large/pseudoceros-ferrugineus.jpghttp://www.waterworxbali.com/Images/Photos/Large/pseudoceros-ferrugineus.jpg

  14. Gastrovascular cavity with only 1 opening; absorb materials across tissue. • Flatworms are divided into four classes: Turbellaria, Monogenia,Trematoda (flukes), and Cestoidea (tapeworms).

  15. Turbellaria http://en.wikipedia.org/wiki/Turbellaria

  16. Trematoda http://en.wikipedia.org/wiki/Trematodes

  17. Cestoidea http://www.saudeanimal.com.br/imagens/platelmintos.jpg

  18. Planaria - scavengers found in ponds. • No organs specialized for circulation or respiration; exchange gases across membranes. • Have eyespots for detecting light and lateral flaps for smell. • Nervous systems more advanced than cnidarians; reproduce asexually through regeneration (can sexually reproduce).

  19. Planaria

  20. Trematodes parasites with suckers to attach to victims. • Blood fluke - parasite of humans. • Tapeworms have suckers and hooks on head; anchor worm in digestive tract of host.

  21. Blood fluke

  22. 5Phylum Rotifera • Rotifers - complete digestive tract with separate mouth and anus. • Internal organs in pseudocoelom - body cavity not completely lined with mesoderm. • Functions as circulatory system -nutrients dissolved in cavity. • Have hydrostatic skeleton - movement.

  23. http://planktonweb.ifas.ufl.edu/Asplanchna.jpg

  24. Some rotifers exist only as females that produce more females from unfertilized eggs - parthenogenesis.

  25. 6Phylum Mollusca • Snails, slugs, clams, squid, and octopus. • Mollusks soft-bodied animals - most protected by hard shell of calcium carbonate. • All have similar body plan with muscular foot (locomotion), visceral mass with most of internal organs, and mantle.

  26. http://sps.k12.ar.us/massengale/clip0051.jpg

  27. Use radula to feed - allows them to scrape up food. • Most mollusks have separate sexes. • 4 common classes - Polyplacophora (chitons), Gastropoda (snails and slugs), Bivalvia (clams, oysters, and other bivalves), Cephalopoda (squids, octopuses, and nautiluses).

  28. Chiton

  29. http://cache.eb.com/eb/image?id=65301&rendTypeId=4 Gastropod

  30. http://www.marinefoundation.org/mussels_600.jpg Bivalves

  31. Cephalopod http://home.earthlink.net/~snailstales/cephalopods.jpg

  32. Gastropods have shells that they can retreat into (means stomach-foot) • Lining of mantle acts like lungs - allows them to live on land (garden snails and slugs).

  33. Bivalves - 2-shelled - clams, oysters, mussels, and scallops. • Most bivalves - suspension feeders, trapping fine particles in mucus that coats gills. • Usually sessile - cannot move during lifetime.

  34. Cephalopods have reduced shell and include nautilus, squid, and octopus. • Nautilus - external shell. • Have well-developed nervous system with complex brain and well-developed sense organs. • Cephalopods have closed circulatory system.

  35. Nautilus

  36. 6Phylum Annelida • Annelids - segmented worms. • Digestive system - pharynx, esophagus, crop, gizzard, and intestine. • Closed circulatory system with 5 chambers act as heart to pump blood.

  37. http://www.inhs.uiuc.edu/~sjtaylor/cave/cave_olig.jpg

  38. Each segment - pair of excretory tubes, (metanephridia) - remove wastes from blood and coelomic fluid exits through pores. • Brainlike pair of cerebral ganglia lie above and in front of pharynx. • Some earthworms reproduce asexually (regeneration), also reproduce sexually.

More Related