1. Invertebrates

3.  Make up about 97 % of all animal species

4. Phylum Porifera  Sponges  Simplest animals  Do not have tissues or organs  Asymmetrical  Have pores through which they filter food and absorb oxygen  Reproduces sexually through gametes or asexually through budding/fragmenting  Are usually hermaphrodites

5. Phylum Porifera  Filter feeders  Sessile as adults, meaning they don’t move and are stuck to a surface

6. Phylum Porifera

7. Phylum Cnidarian  Includes jellyfish, corals, hydras  All live in water  Reproduce sexually for the most part, but can reproduce asexually through budding  radial symmetry  sting

8. Phylum Cnidarian

9. Nematocysts, coiled and uncoiled

10. Phylum Platyhelminthes  Flatworms  Flat, thin bodies  bilateral symmetry (simplest animal with this)  Usually hermaphrodites  Reproduce sexually or asexually through regeneration

11. Phylum Platyhelminthes  Ex: planarians, flukes, and tapeworms.  Most are parasites

12. Phylum Platyhelminthes

15. Phylum Nematoda  Roundworms  Examples: ascaris, pinworms, heartworms and hookworms

16. Hookworms

17. Phylum Nematoda

18.  bilateral symmetry  live in wet soil or watery habitats  Sexual reproduction

19. Phylum Annelid  segmented worms  Live in moist soil, saltwater, and freshwater  Bilateral symmetry  Closed circulation  True digestive system  reproduce sexually  Examples: earthworms and leeches

20. Phylum Annelid

21. Phylum Mollusca  Examples: snails, slugs, oysters, clams, squids, and octopuses  Most live in saltwater and freshwater but some do live on land  bilateral symmetry  have a head, body and muscular “foot”  Have gills (water) or a primitive lung (land)  Open circulation  Sexual reproduction  soft bodies that contain organs  A hard outside shell protects most mollusks

22. Phylum Mollusca

24. Phylum Arthropoda Largest group of invertebrates segmented bodies with jointed legs, which add flexibility exoskeleton contains chitin, the same sugar found in fungi cell walls (and nowhere else) must Molt which is when they shed the old exoskeleton, after the new one has grown beneath it.

25. Molting…

26. Phylum Arthropoda  Three main groups:  Crustaceans  Arachnids  Insects  More groups are out there, but….

27. Crustaceans  Examples: Lobsters, crabs, crayfish, rolypolys (pillbugs)  Must live in water or moist areas  Most have 5 pairs of legs, but often the first pair is modified into claws  Two OR three body segments, depending on species

28. Crustaceans

29. Arachnids  spiders, mites, ticks, scorpions, granddaddy long legs (harvestmen)  Six pairs of jointed appendages, 4 pairs of which are legs.  2 body segments—cephalothorax and abdomen

30. Arachnids

31. Insects  Live almost everywhere, except in the deep ocean  Ex.: mosquitoes, flies, ants, and beetles  6 legs  3 body segments  Since insects can fly, they can escape predators— why they are successful! (only invertebrate that can fly!)  Find food  Find new habitats

32. Insects  Metamorphosis: a series of chemicallycontrolled changes in body structure from juvenile to adult

33. Insects  Complete metamorphosis: the changes in the animal’s form in which earlier stages do not look like the adult  Four stages: egg, larva, pupa, adult  Ex.: butterfly

35. Insects  Incomplete metamorphosis: the young insects resemble the adults  3 stages: egg, nymph, adult  A nymph hatches from the egg with the same general appearance as the adult, only smaller  Ex.: grasshoppers, cockroaches

37. Insects  Many insects are pests  Fleas, ticks, and mosquitoes carry microorganisms that cause disease  Grasshoppers and caterpillars destroy crops

38. Insects  Many insects are the food source for other organisms  Other insects are useful. Ex.: make honey, wax, silk  Insects pollinate flowers that produce fruits

39. Phylum Echinodermata  Sea urchins, sand dollars, sea cucumbers, and sea stars  Live in marine environments  Name means spiny skin  No body segments  Radial symmetry  have spines  Have mouth, stomach, intestines, but no head/brain  Reproduce sexually or asexually through regeneration

40. Phylum Echinodermata

42.  Have an endoskeleton  Have tube feet to attach firmly to surfaces and also to move  Tube feet are like suction cups