| A | B |
|---|
| Birds | A bird is an endothermic vertebrate that has feathers and a four-chambered heart, and lay eggs |
| Contour feather | A large feather thathelps give shape to a birds body |
| Down feather | Short, fluffy feathers that trap heat and keep a bird warm |
| Insulator | A material that does not conduct heat well and thus helps to prevent heat from escaping |
| Crop | A bird’s internal storage tank that allows it to store food inside its body after swallowing |
| Gizzard | A thick-walled, muscular part of a birds stomach that squeezes and grinds partially digested food |
| Mammals | An endothermic vertebrate with a four-chambered heart, skin covered with fur or hair, and has young fed with milk from the mother’s body |
| Incisors | Flat-edged teeth used to bite off an cut parts of food |
| Canines | Sharply pointed teeth that stab food and tear into it |
| Premolars | Teeth that, along with molars, grind and shred food into tiny bits |
| Molars | Teeth that, along with premolars , grind and shred food into tiny bits |
| Diaphragm | A large, dome-shaped muscle that plays an important role in breathing |
| Mammary Glands | The organs that produce the milk with which mammals feed their young |
| Monotremes | A mammal that lays eggs |
| Marsupials | A mammal whose young are born alive at an early stage of development, and which usually continue to develop in a pouch on their mother’s body |
| Gestation period | The length of time between fertilization and the birth of a mammal |
| Placenta | A membrane that becomes the link between the developing embryo or fetus and the mother |
