| A | B |
|---|
| Endothermic | "warm-blooded"; able to maintain a constant, internal body temperature |
| Incubate | to keep an organism in a favorable environment for growth & development |
| Contour Feathers | feathers that birds use for flight & coloration |
| Downy Feathers | soft, fluffy feathers close to a bird's skin; provide warmth |
| Preening | the process of placing oils on feathers so that they can repel water |
| Hollow Bones | special bones that birds have; enable birds to fly |
| Mammal | a type of animal that produces milk to feed young |
| Mammary Glands | special glands that produce milk for offspring |
| Sweat Glands | glands that allow for sweat to be released through the skin |
| Scent Glands | special glands that release various types of scents (smells, odors, etc.) through the skin |
| Blubber | a thick layer of fat that acts as an insulator for some mammals |
| Insulation | providing warmth |
| Monotreme | the "extreme mammal"; lays eggs and doesn't have nipples |
| Monotreme Example | platypus |
| Marsupials | mammals that give birth to immature young then carry them in the mother's abdominal pouch |
| Marsupial Examples | kangaroos, Tasmanian devils, opossums, koala bears |
| Placental Mammals | mammals where the young will completely develop within the mother's body; use umbilical cord to connect to mother's placenta |
| Placental Examples | humans, cats, dogs, whales, pigs, cows |
| Placenta | the special organ that supplies a developing baby with oxygen & nutrients during pregnancy |
| Umbilical Cord | the structure that connects the developing baby to its mother's placenta; is cut at birth to form the "belly button" |
| Gestation Period | the period of time a female is pregnant; example- the gestation period for a human is 9 months |
