Mod 2 Slide Set 2 Survey of Animal Kingdom Introduction; Porifera-Nematoda

1. Mod 2 Slide Set 2Survey of Animal KingdomIntroduction; Porifera-Nematoda See Mod 2 Learning Objectives at Blackboard Read Ch. 17 Do Ch 17 activities and quizzes at MasteringBiology

2. Characteristics of Animals • Multi-celled, heterotrophic, eukaryotes • Require oxygen for aerobic respiration • Reproduce sexually, and perhaps asexually • Motile at some stage • Develop from embryos • Animal cells lack the rigid cell wall found in plant cells.

3. 9 Major Phyla of AnimalsPorifera(sponges)Cnidaria(jellyfish, corals, etc)Platyhelminthes(flatworms)Nematoda(roundworms)Mollusca(mollusks)Annelida(segmented worms)Arthropoda(Bugs, crabs, etc)Echinodermata(starfish, etc.)Chordata(fish, tetrapods, etc.) Chordates Echinoderms Arthropods Annelids Coelomate Ancestry Mollusks Rotifers Roundworms Bilateral Ancestry Flatworms Radial Ancestry Cnidarians Sponges Multicelled Ancestry Single-celled, protistan-like ancestors

4. Overview of the Animal Kingdom

5. Another view ofthe A.K. Sponges No true tissues Cnidarians Radial symmetry Ancestral Protist Molluscs Flatworms Tissues Annelids Roundworms Arthropods Bilateral symmetry Echinoderms Chordates

6. Animal Architecturesupra-phyletic features(“above-the-phylum” features) • LEVELS OF ORGANIZATION • Animals range from simple to complex in their organization. • Cellular Level: (of organization) Sponges • Tissue Level: Cnidaria • Organ Level: Flatworms, Roundworms, Segmented worms, Molluscs, Arthropods, Echinoderms, Chordates

7. Animal Architecturesupra-phyletic features EMBRYOLOGICAL ARCHITECTURE • Diploblastic or Triploblastic? • 2 germ layers or 3 germ layers • Acoelomate, Pseudocoelomate, Eucoelomate? • No, false, or true… body cavity (coelom) • Protostome or Deuterostome? • Blastopore becomes mouth or it becomes anus. • Symmetry • None, Radial, Bilateral • Segmentation

8. a Eggs form and mature in female reproductive organs, and sperm form and mature in male reproductive organs. Gamete formation Germ Layers b A sperm and an egg fuse at their plasma membrane, then the nucleus of one fuses with the nucleus of the other to form the zygote. Fertilization frog sperm c By a series of mitotic cell divisions, different daughter cells receive different regions of the egg cytoplasm. Cleavage d Cell divisions, migrations, and rearrangements produce two or three primary tissues, the forerunners of specialized tissues and organs. Gastrulation midsectional views e Subpopulations of cells are sculpted into specialized organs and tissues in prescribed spatial patterns at prescribed times. Organ Formation top view side view Growth, tissue Specilazation f Organs increase in size and gradually assume specialized functions. Fig. 43-4, p.758

9. GeneralizedEmbryologicalDevelopment fertilization, zygote cleavage stages, 2, 4, 8, etc. morula(solid ball of cells) blastula (hollow ball of cells) with blastocoel (central cavity) gastrulation, gastrula archaenteron (gut) formation of germ layers ectoderm endoderm mesoderm

10. A gastrula Looks like this this hole is the blastopore p.769

11. Embryonic Germ Layers and the Tissues They Produce • Ectoderm (“outer skin” the outer germ layer) • Skin, • Nervous system • Endoderm • Lining of digestive syst. • Lining of lungs, etc • Mesoderm • Cardiovascular • Bone • Muscle, etc • If an animal forms from an embryo of just 2 germ layers it is said to be diploblastic • If an animal forms from an embryo of 3 germ layers it is said to be triploblastic

12. Symmetry, radial or bilateral? Fig. 25-5, p.406

13. Radial vs Bilateral Symmetry

14. The Gutnone, saclike, or tubular? • Region where food is digested and then absorbed. It can be a… • Saclike gut: (the digestive system has one opening) • One opening for taking in food and expelling waste. e.g. Cnidaria, Platyhelminthes • Tubular gut: (the digestive system has two openings) • Opening at both ends; mouth and anus e.g. Arthropoda, Chordata, Nematoda, Mollusca, Echinodermata, Annelida.

15. The Body Cavity or Coelomacoelomate, pseudocoelomate, eucoelomate

16. Segmentation • Repeating series of body units • Units may or may not be similar to one another • Earthworms - segments appear similar • Insects - segments may be fused and/or have specialized functions • Annelida, Arthropoda, Chordata

17. Segmentation(it evolved more than once; it must work pretty well !) sponges cnidarians flatworms annelids mollusks roundworms arthropods echinoderms chordates coelom reduced coelom reduced pseudocoel coelom lost molting PROTOSTOMES mouth from blastopore DEUTEROSOMES anus from blastopore radial ancestry, two germ layers bilateral, coelomate ancestry, three germ layers true tissues multicelled body Fig. 25-7, p.407

18. Segmentationarose early, Ediacaran Fossils, 600-500 myp Fig. 25-8a, p.407, Spriggina Fig. 25-8b, p.407,Dickinsonia

19. Segmentationan early trilobite fire worm Fig. 25-8c, p.407

20. Segmentation

21. Segmentation

22. Segmentation

23. Survey of the Major Animal Phyla

24. Know these 9:PORIFERACNIDARIAPLATYHELMINTHESNEMATODAMOLLUSCAANNELIDAARTHROPODAECHINODERMATACHORDATA

25. Sponges No true tissues Cnidarians Radial symmetry Ancestral Protist Fig. 17-05 Molluscs Flatworms Tissues Annelids Roundworms Arthropods Bilateral symmetry Echinoderms Chordates

26. Animal Origins • Originated during the Precambrian(1.2 billion - 670 million years ago) • From what? Two hypotheses: • Multinucleated ciliate became compartmentalized • Cells in a colonial flagellate became specialized

27. Animal Origins 3. Choanocytes 1. Choanoflagellates 2. Proterospongia Volvox, a colonial green alga

28. Animal Origins • The peculiar flagellated collar cell is found in: • Choanoflagellates, single celled-Protists • Proterospongia, a colonial organism • 3. Choanocytes of Sponges, a multi-celled animal Fig. 25-4a, p.405

29. Animal Origins Choanoflagellatesa Unicellular Protist Fig. 25-4b, p.405

30. Animal Origins Proterospongia a colonial array of choanoflagellates around a central gelatinous matrix Fig. 25-4c, p.405

31. p.408

32. Phylum Poriferasponge1 sponge2 Widespread, benthic, sessile filter-feeders. w/ choanocytes ! Cellular level of organization No symmetry No tissues No organs all aquatic, mostly marine, a few live in freshwater. Reproduce sexually (and asex) Microscopic swimming larval stage Fig. 25-9a, p.408

33. Sponge Structure

34. Cellular Organizationcan reproduce asexually by fragmentation

35. Usually Sexual Reproduction

36. Boring Sponge Fig. 25-9b, p.408

37. Tube Sponge Glass Sponge Skeleton Fig. 25-9c, p.408

38. mesoglea-filled bell Phylum Cnidaria”No head, no anus, no problem !” tentacles Radial Symmetry Tissue Level of Organization Diploblastic Mesoglea Sac-like Gut Stinging cells (nematocysts) Polyp and/or Medusa stages Fig. 25-13b, p.410

39. Two Main Body PlansPOLYP stage usually asexual MEDUSA stage is sexual Polyp outer epithelium (epidermis) mesoglea (matrix) Medusa inner epithelium (gastrodermis) Fig. 25-12, p.410

40. Phylum Cnidarianematocysts • Only animals that produce nematocysts capsule’s lid at free surface of epidermal cell trigger barbed thread inside capsule nematocyst Fig. 25-13, p.410

41. Cnidarian Diversity3 main groups… • Scyphozoans (“cup animals”) • (medusa is dominant stage, polyp is reduced) • True Jellyfish • Anthozoans (“flower animals”) • (polyp stage only, no medusa) • Sea anemones • Corals • Hydrozoans (“water animals”) • (polyp is the dominant stage, medusa is reduced) • Hydroids • Fire Coral • Portugese man o’ war

42. Phylum Cnidaria: Coral Polyps

43. Obelia Life Cycle (Hydrozoan) male medusa female medusa reproductive polyp sperm ovum zygote feeding polyp polyp forming planula Fig. 25-15a, p.411

44. Reproduction in Hydra sp.

45. Feeding in Hydra Sea anemone feeding on fish youtube Fig. 25-14a2, p.411

46. The Portugeseman-o-war is a colonial hyrozoan. The painful/deadly box jellies of Australia are hydroza too. Fig. 25-14b, p.411

47. Flatworms: Phylum Platyhelminthes • Acoelomate, bilateral, cephalized animals • Organ Level of Organization All have simple or complex organ systems • Most are oviparous hermaphrodites

48. Flatworms are acoelomate, bilateral and have a saclike gut

49. Planarian Organ SystemsFlatworms have much more sophisticated organ systems than Cnidaria. Cnidaria are at the tissue level of organization while flatworms are at organ level of organization. Reproductive System Digestive System Nervous System Excretory System Fig. 25-16, p.412

50. Four Major Groups • Turbellarians (Turbellaria) • E.g. the Planaria, etc. • Flukes (Trematoda) • E.g. Chinese Liver Fluke, etc. • Monogenea • Gyrodactylus • Tapeworms (Cestoda) • E.g. Beef tapeworm, fish tapeworm, etc. Gyrodactylus Fish tapeworm Planaria Chinese live fluke