click below
click below
Normal Size Small Size show me how
Kingdom Animalia
Exam 4 Study Guide
| Question | Answer |
|---|---|
| What are the physical characteristics that are unique to mammals? | Cell migration and embryonic stem cell layers |
| What evolutionary traits and strategies did mammals evolve to adapt to their environment and to be more successful at reproduction? | Two types of embryonic development: Protostomes and deuterostomes (develop digestive system in different directions. |
| What is meant by "ectothermic" or "endothermic"? | ectothermic= body temperature matches environment and endothermic= warm-blooded |
| Are mammals ectothermic or endothermic? | endothermic |
| What specific vertebrate group is the ancestor of mammals? | therapsid reptiles |
| Which evolved first - birds or mammals? | mammals |
| Did mammals co-exist with dinosaurs? | Yes, but in the shadows |
| Did primates co-exist with dinosaurs? | No |
| What are the characteristics of class mammalia? | endothermic, have fur, sweat glands, internal fertilization and parental care, and mammary glands |
| Examples of characteristics of class mammalia. | lizard pressed against warm rocks gains heat; sweating human cooled by evaporation |
| What was the order of evolution of these groups? | monotremes, marsupials, and eutherians (placentals) |
| Where are monotremes and marsupials found today? | Australia, Tasmania, New Guinea, and New Zealand |
| Monotremes: | egg-laying mammals that nourish young with milk from mammary glands. Ex: duck-billed platypus, short-beaked echidna |
| Marsupials: | protect and feed young with milk from mammary glands in external pocket/pouch. Ex: possum, opossum, koala bear, kangaroo, and sugar glider |
| Placentals: | nourish young internally during embryonic and fetal development through placenta. Ex: polar bears |
| What is a "placenta"? | a temporary organ comprised of embryonic and maternal tissues with an extensive blood supply |
| What did the placenta evolve from? | amniotic egg |