After reading this chapter and analyzing the content, it is assumed that you can:

1. Define epigenesis.
   
   
2. Describe how early preformation ideas differed from Kaspar Friedrich Wolff's concept of epigenesis.
   
   
3. Explain the preparation of the oocyte for fertilization.
   
   
4. Describe the events that occur following the contact of a spermatozoon with a secondary oocyte.
   
   
5. Explain how polyspermy is prevented.
   
   
6. Describe "activation" in embryology.
   
   
7. Explain how the amount of yolk affects cleavage.
   
   
8. Differentiate between spiral and radial cleavage.
   
   
9. Explain indirect development.
   
   
10. Describe the process of gastrulation.
    
    
11. Differentiate between the schizocoelous and enterocoelous origins of the coelom.
    
    
12. Describe experimental approaches to create evidence for nuclear equivalence in animal embryos.
    
    
13. Explain "induction" in embryology.
    
    
14. Explain homeotic genes and the function of the "homeobox" contained within genes.
    
    
15. Explain the evolutionary significance of Hox genes.
    
    
16. Describe the embryological evidence that vertebrates form a monophyletic group.
    
    
17. List the four extraembryonic membranes of amniotic eggs of birds and nonavian reptiles and be able to give the function of each.
    
    
18. Explain how the "growth cone" influences the direction of nerve growth.
    
    
19. Know which germ layers are responsible for creating all the organ systems.
    
    
20. List the developmental characteristics that are used to divide animals into protostome or deuterostome clades.