2. I. General Characteristics of Animals
A.Heterotrophic- Must take in food
B.Mobility- Most animals can perform rapid, complex movements
C.Multicellularity- Made of more than one cell
D.Eukaryotic- Made of true cells with nucleus and organelles
3. II. Invertebrates
Animals without a backbone
4. III.Invertebrate Characteristics
A. Internal Body Cavities
1. coelom- body cavity
A. acoelomates- animals with no body cavity
B. pseudocoelomates- animals with a false body cavity
C. coelomates- animals with a true body cavity
5. B. Skeletons
1. hydrostatic- use water contained under pressure
2. exoskeleton- a rigid external skeleton
3. endoskeleton- an internal skeleton
exoskeleton
endoskeleton
6. C. Body Symmetry
1. asymmetrical- irregular in shape
2. radial- body parts arranged around a central axis
Bilateral- right and left sides that are mirror images
7. Body Symmetry
8. 9. D. Feeding and Digestion
1. intracellular digestion- digestion within special body
cells
2. gastrovascular cavity- a digestive sac with only a single
opening
3. extracellular digestion- food is digested by special
organs
10. E. Circulatory System
1. open system- blood is not contained in vessels
2. closed system- heart circulates bloodinside blood vessels
11. F. Methods of Respiration
1. respire through the skin (earthworm)
2. use gills (crayfish, fish)
3. book lungs (spider)
4. trachea (insects)
12. Methods of Respiration
gills
Book lungs
13. F. Methods of Excretion
1. flame cells
2. nephridia
3. malpighian tubules
14. Methods of Excretion
15. H. Response
1. centralization- concentration of nerve cells at anterior
end
2. cephalization- anterior developed into a definite head
16. I. Types of Reproduction
1. asexual-clone of the parent
regeneration: can regrow lost body parts
Budding :seperation of a parent into 2 or more individuals
2. hermaphrodites- contains male and female parts
3. sexual- fusion of egg and sperm
17. IV. Invertebrate Phyla
A. Porifera- sponges
18. B. Cnidarian- jellyfish, corals, sea anemone
19. C. Platyhelminthes- flatworms-planaria, tapeworm
20. D. Nematodes- roundworms
21. E. Annelids- segmented worms-earthworms, leeches
22. F. Mollusks- clams, snails, squid
23. G. Echinoderms- starfish, sea urchin, sand dollar
24. H. Arthropods- spider, grasshoppers
