1. How many lines of symmetry?

2. Fertilized egg Zygote is one diploid cell made by the fusion of the sperm and egg. In humans this is internal fertilization within the fallopian tubes. Many other organisms have external fertilization where the egg and sperm are both released outside the parent.

3. blastula 8 cell stage (blastocyst) morula gastrula

4. Germ layers 3 kinds: –Ectoderm –Mesoderm –Endoderm –Layers of cells that work together to form specific tissues. –Sponges (0), cnidarian (2), others (all three)

6. Body plans: Coelom

7. If three germ layers, then….

8. Porifera Sponges Sessile Adults Motile Larvae Assymetry Very Primitive- “barely” multicellular Classified by hard skeletal spines called spicules

9. spicules

10. Investigating sponges http://www.youtube.com/watch?v=BW05vMziy2o Sponges spawning http://www.youtube.com/watch?v=SHJOu9PjKyU

11. Body of sponge Osculum: opening at the top Ostia: openings in the wall of sponge

12. Cnidaria Alternation of generations: Most have both stages in life cycle Medusa: motile/sexual/tentacles down/mouth down Polyp: sessile/asexual/ mouth up/tentacles up

13. Characteristics of Cnidaria Nematocyst stingers Nerve net (no brain)

14. Hydra Hydra catching food: http://www.youtube.com/watch ?v=Kukv0AtIVdU&feature=relat ed http://www.youtube.com/watch ?v=Kukv0AtIVdU&feature=relat ed Hydra; http://www.youtube.com/watch ?v=yqXkaZwiu6s&feature=relat ed http://www.youtube.com/watch ?v=yqXkaZwiu6s&feature=relat ed

15. http://www.youtube.com/watch?v=v9j9iO6 Zy4o&feature=PlayList&p=E9E1093124E 2F9C9&playnext=1&index=3; jellyfish movementhttp://www.youtube.com/watch?v=v9j9iO6 Zy4o&feature=PlayList&p=E9E1093124E 2F9C9&playnext=1&index=3 http://www.youtube.com/watch?v=M9MM p7QX6e0&feature=PlayList&p=E9E10931 24E2F9C9&playnext=1&index=2 polyp stagehttp://www.youtube.com/watch?v=M9MM p7QX6e0&feature=PlayList&p=E9E10931 24E2F9C9&playnext=1&index=2

17. Cnidarians

18. Portuguese Man-of-War are colonies of four kinds of highly modified polyps: feeding polyps, reproductive polyps, etc.. Hydra Hydra catching food: http://www.youtube.com/watch ?v=Kukv0AtIVdU&feature=relat ed http://www.youtube.com/watch ?v=Kukv0AtIVdU&feature=relat ed Cnidaria: hydrozoa

19. Phylum Ctenophora: close relatives to cnidaria but jelly instead of stingers Comb jellies http://www.youtube.com/watch?v=G7WT81ukHZE

20. PlatyhelminthesFLATWORMS Tapeworms, Flukes (parasites), free swimming (planaria)

21. Cephalization Notice the front end has sensory organs (HEAD?) Most are parasitic and don’t have cephalization, but platyhelminthes were first to have it.

22. Characteristics Acoelomate/ No coelom/organs Highly branched Digestive system as they have no circulatory system

23. Flatworm videos http://www.youtube.com/watch?v=voMKJe a91gg free living flatwormhttp://www.youtube.com/watch?v=voMKJe a91gg http://www.youtube.com/watch?v=Ich4Y_ K6GuM&feature=PlayList&p=E9E1093124 E2F9C9&playnext=1&index=11 planaria eatinghttp://www.youtube.com/watch?v=Ich4Y_ K6GuM&feature=PlayList&p=E9E1093124 E2F9C9&playnext=1&index=11 http://www.youtube.com/watch?v=T6pAfQI nf2c tapeworm in intestinehttp://www.youtube.com/watch?v=T6pAfQI nf2c

24. Fluke All parasitic Most famous is the Sheep liver fluke that causes schistosomiasis. Over 100 million in the world have this fluke/disease.