| A | B |
|---|
| vertebrate | an animal that has a backbone. |
| invertebrates | an animal without a backbone |
| Multicellular | animals that are made of many cells. |
| embryo | a plant or animal at an early stage of development. |
| organ | a group of tissues that carry out a special function of the body. |
| consumer | an organism that eats other organisms or organic matter. |
| innate behavior | an inherited behavior that does not depend on the envirnment or experience. |
| learned behavior | a behavior that has been learned from experience. |
| territory | an area that is occupied by one animal or a group of animals that do not allow other members of the species to enter. |
| predators | Animals that eat other animals. |
| prey | An animal that is being eaten. |
| courtship | A behavior that animals use to help them find a mate |
| migrate | to travel from one place to another. |
| landmarks | fixed objects that an animal uses to find its way. |
| hibernation | a period of inactivity and lowered body temperature that some animals undergo in winter as a protection against cold weather and lack of food. |
| estivation | a period of inactivity and lowered body temperature that some animals undergo in summer as a protection against hot weather and lack of food. |
| circadian rhythm | a biological daily cycle. |
| biological clock | an internal control of an animal's natural cycles. |
| social behavior | the interaction between animals of the same species |
| communication | a transfer of a signal or message from one animal to another that results in some type of response. |
| pheromone | a substance that is released by the body and that causes another individual of the same species to react in a predictable way. |
