1. Kingdom Animalia
Lower Invertebrates

2. Characteristics: eukaryotic multicellular heterotrophic consumers
no cell walls
sexual and asexual reproduction
locomotion
99% invertebrates

3. Symmetry of body plan:
asymmetry – no symmetry
radial – central point; can be divided into equal
sections
bilateral – can be divided into 2 mirrored halves
cephalization – concentration of sense organs
toward anterior end (associated with development
of a head)

5. anterior – region of a bilaterally symmetrical
organism toward the head end
posterior – region of a bilaterally symmetrical
organism toward the tail end
dorsal – back side of a bilaterally symmetrical
organism
ventral – under side of a bilaterally symmetrical
lateral – to the side of a bilaterally symmetrical

6. A. Phylum Porifera sponges simplest animals
adults sessile, filter feeders (larvae are free-swimming)
water vascular system – pumps large amts. of water through porous body; all aquatic
asymmetrical

8. A. Phylum Porifera…cont
composed of spicules – framework of the sponge
classified by spicule composition:
reproduce sexually by egg and sperm
asexually by budding

10. B. Phylum Cnidaria corals, jellyfish, anemones radial symmetry
entirely aquatic (marine, few fw)
possess stinging cells (nematocysts) on tentacles
nerve net – simple nervous system

12. B. Phylum Cnidaria classified by life cycle stages:
1) medusa – free swimming
2) polyp – attached stage
reproduction:
asexually by budding
sexually by egg & sperm

14. C. Phylum Platyhelminthes
flatworms
incomplete digestive system (one opening)
bilateral symmetry

16. D. Phylum Nematoda roundworms complete digestive system – 2 openings
bilateral symmetry
tube within a tube body plan
ex: Ascaris, hookworms, filarial worms, eyeworms, Trichinella – cause trichinosis

17. E. Phylum Annelida segmented worms name means “little ring”
true coelom – fluid-filled body cavity
complete digestive system
all organ systems present
closed circulatory system – blood is confined to vessels

18. E. Phylum Annelida
classified by their number of setae – bristles for locomotion