| A | B |
|---|
| habitat | a place that an organism lives and that provides the things the organism needs |
| biotic factors | living parts of an ecosystem |
| abiotic factors | the nonliving parts of an ecosystem |
| populations | all the members of one species in a particular area are referred to as |
| community | all the different populations in the area make up this |
| ecology | the study of how living things interact with one another and with their environment |
| population density | the number of individuals in a specific area |
| estimate | an approximation of a number based on reasonable assumptions |
| birth rate | the number of births in a population in a certain amount of time |
| death rate | the number of deaths in a population in a certain amount of time |
| immigration | moving into a population |
| emigration | leaving a population |
| limiting factor | an environmental factor that prevents a population from increasing |
| carrying capacity | the largest population that an environment can support |
| natural selection | the process by which individuals that are better adapted to their environment are more likely to survive and reproduce than other members of the same species |
| niche | an organism's particular role in an ecosystem, or how it makes its living |
| competition | the struggle between organisms for the limited resources in a habitat |
| predation | an interaction in which one organism hunts and kills another animal for food |
| predator | a carnivore that hunts and kills other animals for food and has adaptations that help it capture the animals it preys upon |
| prey | an animal that a predator feeds upon |
