| A | B |
|---|
| dinosaurs | famous and spectacular reptiles found during the Mesozoic era |
| asteroid-impact hypothesis | catastrophic cosmic event responsible for the mass extinction when an asteroid hit the Earth sending so much dust to the atmosphere that the amount of sunlight reaching the Earth's surface was greatly reduced |
| amniotic eggs | encase the embryo in a secure, self-contained aquatic environment |
| amnion | the thin membrane enclosing the fluid in which the embryo floats |
| yolk sac | encloses the yolk, a fat-rich food supply for the developing embryo |
| allantois | stores the nitrogenous wastes produced by the embryo |
| chorion | surrounds all the other membranes and helps protect the developing embryo |
| albumen | where protein and water needed by the embryo are contained |
| keratin | protein that forms your fingernails and hair and is also in the surface cells of reptiles |
| septum | in lizards, snakes, tuataras, turtles, the heart has two artia and a single ventricle partially divided by a wall of tissue |
| alveoli | the lining of the lungs may be folded into numerous small sacs |
| Jacobson's organ | a specialized sense organ located in the roof of the mouth of reptiles |
| thermoregulation | the control of body temperature |
| ectotherm | warms its body by absorbing heat from its surroundings |
| endotherms | have a rapid metabolism which generates heat needed to warm the body |
| oviparity | the female's reproductive tract encloses each egg in a tough protective shell, the female then deposits the eggs in a favorable place in the environment |
| ovoviviparity | when the female retains the eggs within her body for a time and the eggs are laid shortly before hatching occurs |
| viviparity | a shell does not form around the egg, and the young are retained within the female's body until they are mature enough to be born |
| placenta | nutrients and oxygen are transferred from mother to embryo through this structure |
| carapace | top, or dorsal, part of the shell |
| plastron | the lower, or ventral portion of the shell |
| autotomy | if threatened by a predator, some lizards have the ability to detach their tail |
| constrictors | snakes that wrap their bodies around prey |
| Elapid | snakes that inject poison through 2 small fixed fangs in the front of the mouth |
| Vipers | snakes that inject venom through large mobile fangs in the front of the mouth |
