Ch 28 Answers:
1.a 2.b 3.c 4.c 5.a 6.b
7.c 8.d 9.c 10.b 11.d 12.F
13.T 14.F 15.T 16.T 17.F 18. T
19.F 20.F 21.F 22.T
23. Tissue
24. Excretory System
25. Hydrostatic skeleton
26. Blastula
27. dorsal, ventral, anterior, posterior
28. Cell walls
29. Circulatory system
30. Mesoderm
31. Radial Symmetry
32. Vertebral Column
33. Excretory System
34. Hermaphrodite
35. Primary tissue layers
36. Gills
37. True Coelom
38. Diploidy means having two copies of each chromosome. One copy comes from mother, one comes from father. Advantage-new combinations of genes occur.
39. The animal kingdom is divided into invertebrates (no backbone) and vertebrates (backbone). To determine evolutionary relationships, scientists consider tissues, type of symmetry, presence of a body cavity, segmentation, and jointed appendages.
40. During external fertilization, males and females release gametes near each other. Only a few fertilized eggs survive and develop. Large numbers of gametes must be released by males and females to increase odds of reproductive success.
41. Hydrostatic skeleton- hydra, earthworm
Exoskeleton- clams, crabs, insects
Endoskeleton- humans and all other vertebrates
42. Heterotrophy, mobility, multicellularity, diploidy, sexual reproduction, absence of a cell wall, blastula formation, tissues
43. A-radial B- bilateral C- asymmetrical
