CHAPTER 5 and 6

1. composed of concentric rings or circuli.
3. type of feather that aerodynamically shape the surface of the bird.
7. characterized by the prevalance of thick surface coat enamel,without an underlying layer of dentin.
9. a cap of cells arched over a small blastocoel.
12. process of forming an ectodermal tube,the neural tube.
13. the act of giving birth via viviparity.
15. the down feathers.
17. produce an oily secretion,sebum.
18. union of two or more gametes.
19. with a fringe of projection along its posterior margin.
21. female gamete.
25. are slender,keratinous filaments.
26. tissues that includes bones,cartilage,fibrous connective tissue,adipose tissue and the blood.
28. the cells resulting from these early cleavage divisions of the ovum.
31. type of feather that constitute the major aerodynamic surfaces.
33. meaning "gut" and "formation".
34. male gamete.
35. the act of laying eggs.
36. release of milk to a suckling.
38. has only single secretory cell.
39. type of feather lie close to the skin as thermal insulation.
40. meaning "tissue formation".

2. "bone formation".
4. beneath the guard hairs and usually much finer and shorter.
5. tissues are formed of closely adjoined cells with every little extracellular matrix between them.
6. meaning "organ" and "formation".
8. a diverse cell found in the skin of lampreys and other fishes.
10. the contour feathers.
11. it lacks on enamel,dentin and a vascular bone layer.
14. a process wherein various protein products accumulate and collectively form keratin.
16. usually found around the snouts of many mammals.
20. meaning "egg" and "birth".
22. meaning "live" and "birth".
23. found in porcupines that are stiff,coarse hairs specialized for defense.
24. a circular pigmented area of skin found around the nipples.
27. the base of a hair.
29. composed of many secretory cells.
30. the time the embryo develops within the female.
32. embryos that draw nutrients from the yolk of the ovum.
37. type of feather that often specialized for display.