The Animal Kingdom What are the factors that define an animal?

1. The Animal Kingdom What are the factors that define an animal? • Animals are multicellular organisms. • Their cells lack a cell wall. • Animals cells are organized into complex organ-systems • Animals are heterotrophic - they must obtain carbon and energy by eating other organisms and absorbing the consumed organisms nourishment. • Animals require oxygen (for aerobic respiration) • Animals can either reproduce sexually or asexually (most are sexual). • Animal life cycles require a period of embryonic development. • Animals are typically mobile

2. Major Aquatic Invertebrate Taxa Phylum Each Phylum has at least one characteristic that sets it apart from the others. This ppt will cover Porifera and Cnidaria Porifera (sponges) – spicules Cnidaria (nahy-dair-ee-uh)(hydra & jellyfish) nematocysts Platyhelminthes (flatworms) Annelida (oligochaetes/leeches) Gastrotricha (gastrotrichs) Nematoda (nematodes) Mollusca (snails/bivalves) Arthropoda (arthropods)

3. Terms Monoecious Diecious Coelom Mesoderm Having both male and female reproductive organs; hermaphrodite Having only one type of reproductive organ; separate and distinct sexes A body cavity lined with a mesoderm Middle layer of germ where organs will rise This slide is not finished!

4. Phylum Porifera From the Latin porus for pore and ferre to bear Animal with pores

5. Phylum Porifera About 5,000 species worldwide About 25 species are freshwater

8. Osculum- • Collar cell or choanocyte- • Amebocytes- • Incurrent pores- where the water leaves the sponge system Vase-shaped cells with a collar of fibrils. Strains out the smallest food items from the water such as individual bacteria. A single flagellum extends and beats, driving the water currents that keep the sponge alive and healthy. These cells are “totipotent”. They can change into all of the other types of cells. Ingest and digest food caught by choanocyte collars. Where water enters the sponge

10. Spicules- • Mesenchyme- • Covering cells or pinacocytes- • Importance to man: • A 10 cm sponge can filter 20 Liters of water a day; many animals live within the cavities of sponges non-living aggregates of a chemical nature, secreted and made from silica, calcium carbonate, or a protein matrix called spongin. acellular gel layer between the outer and inner cell layers ‘skin cells’, thin, leathery and tightly packed.

13. Reproduction All sponges can reproduce sexually Generally monoecious and produce eggs and sperm at different times to prevent self-fertilization Produce flagellated larva that exit via osculum Larval motility is the principal dispersal mechanism Larvae attach to substrate and begin growing Sponges have great powers of regeneration

15. Feeding Sponges feed on fine particulate material in the inflowing water. Food particles generally range from 5- to 50 µm and are phagocytized by amoebocytes. After digestion is complete, the wastes are expelled into the water.

16. Phylum Cnidaria

17. Major Aquatic Invertebrate Taxa Phylum Porifera (sponges) Cnidaria (hydra & jellyfish) Platyhelminthes (flatworms) Annelida (oligochaetes/leeches) Gastropoda (gastropods) Nematoda (nematodes) Mollusca (snails/bivalves) Arthropoda (arthropods)

18. Phylum Cnidaria Over 10,000 species Class Hydrozoa (only freshwater representatives) only 16 freshwater species, the rest of the 10,000 belong to Scyphozoa and Anthozoa Class Scyphozoa (jellyfishes) Class Anthozoa (sea anemones and corals)

19. Cnidaria Classification Kingdom Animalia Phylum Cnidaria Class Hydrozoa Hydra Portuguese Man’o War Class Scythozoa True jellyfish Class Anthozoa Coral Sea anemone

20. Hydra and Jellies Mouth Gastrodermis Tentacle Tentacle Gastrovascular cavity Mesoglea Epidermis Mouth

21. Hydra’s Three Cell Layers • Gastrovascular cavity • open space in interior of hydra • B. Gastrodermis • circular muscle filaments, enzymatic gland cells, neurons, and sensory cells • C. Mesoglea • layer connecting gastrodermis and epidermis • D. Nematocysts • cells within cnidocysts that discharge a toxic, sticky, or barbed filament; hydra is usually toxic • E. Epidermis • epithelial cells, nematocysts, sensory cells, germs cells, neurons

23. Cnidocytes Nematocysts

24. Dimorphismin Cnidaria polyp medusa This structure is an example of Budding!

26. Body Plan in Animals Coelom Pronunciation: Coe-lom (See-lum)

27. Body Cavity Plan Acoelomate • No body cavity present • Organs are in direct contact with the epithelium • Tissues hold organs in place • Ex. Flatworms endoderm mesoderm ectodermto gut • Pseudocoelomate • Possesses a coelom, but it is lined only on the body wall - not around the gut. • Does not possess vascular systems or skeletons. • Ex. Nematodes or roundworms pseudocoel endoderm mesoderm ectoderm gut

30. Body Cavity Plan • Coelom • Possesses a coelom in which both the inside of the body wall and the gut is lined by mesoderm • Tissues called mesenteries suspend organs in the coelom and keep them in place. • Earthworms and higher animals