THE ANIMAL KINGDOM

(Use table)Characteristics of Animals Cell type: Multicellular, eukaryotes Digestion: Heterotrophs Reproduction: Most sexual; some asexual Movement: Usually

Other- 7 things 1. no cell wall 2. Require oxygen

3. Symmetry : balance in body proportions 3 Types Asymmetrical- Irregular shape Radial symmetry: can be divided along any plane to produce 2 halves which look alike Bilateral: can be divided only one way to produce mirror image halves

4. Body arrangements : a. anterior: head region b. posterior: tail region c. dorsal: back or top d. ventral: abdomen or bottom

5. Body Development As embryo develops, three germ layers form: a. Ectoderm becomes nervous system, epidermis of the skin, pituitary, lens of eye b. Mesoderm becomes muscles, skeleton, notochord, circulatory system, kidney, reproductive system c. Endoderm becomes lining of digestive tract, liver, pancreas, epithelial lining of lungs, many endocrine glands

a. Acoelomates- no body cavity lined with mesoderm EX: sponges, cnidarians, & flatworms 6. Body Cavities

b. Pseudocoelomates- partial body cavity lined with mesoderm “Tube within a tube” body plan EX: roundworms

c. Coelomates- true body cavity lined with mesoderm EX: all other animals

Advantages of a body cavity (coelom or pseudocoelom): Fluid in cavity helps distribute food, wastes, hormones, etc. from one end of animal to the other Better distribution allows animal to grow larger A place to put things, like new organs Hydrostatic skeleton- pressure makes cavity rigid

7. Cephalization-concentration of sense organs- developed nervous system 

THE ANIMAL KINGDOM OVERVIEW Invertebrates-no backbone Vertebrates or Chordates-backbone