L100 study guide - Exam three - part three - Animals

1. What characterizes animals?
2. What are the main branch points in the evolution of animals (key tranistions in body plan)?  Understand what adaptive advantages correspond to these major evolutionary steps. For example: What is the difference between a gastrovascular cavity and a complete digestive tract?   What is the selective advantage to having a digestive tract?
3. What is radial vs. bilateral symmetry? Are all animals symmetrical? What is the advantage of bilateral symmetry? How does lifestyle of radially symmetrical organisms differ from bilateral ones?
4. What is cephalization?
5. What is the adaptive advantage of a body cavity?
6. If an animal is described to you, in terms of its general body plan, you should be comfortable with where it would fit on the phylogeny of animal evolution.
   • Animals you should be comfortable with:
     • Sponges
     • Jellyfish (Cnidarians)
     • Flatworms
     • Mollusks
     • Annelids
     • Arthropods / Insects
     • Echinoderms
     • Cartilaginous fishes / sharks
     • Bony Fishes
     • Amphibians
     • Reptiles
     • Birds
     • Mammals
7. What are the characteristics common to all chordates? 
8. What characterizes fishes? What is the difference between cartilaginous fishes and bony fish?  Explain the differences relative to how the organisms are adapted to their environments.  
9. What characterizes amphibians?  Why are they said to have a dual-life? How have they adapted to life on land (at least partially)? Why are they still TIED to water?
10. What characteristics have reptiles evolved as a group that frees them from an absolute dependency on water?   How is being an ectotherm influences its behavior and distribution?
11. What are some adaptations birds have evolved for flight? How are birds similiar to reptiles (what characters do they share)? How are they different?
12. What is the difference between endotherms vs. ectotherms?
13. What is an aminotic egg and what is the advanage of such an egg? Who are the aminotes?
14. What characteristics unify mammals? What is the adaptive significance of these characteristics?
15. What are the three major groups of mammals?