| A | B |
|---|
| Biosphere | part of the Earth that supports life, including the top portion of Earth’s crust, the atmosphere, and all the water on Earth’s surface |
| Carrying capacity | largest number of individuals of a particular species that an ecosystem can support over time |
| Commensalism | a type of symbiotic relationship in which one organism benefits and the other organism is not affected |
| Community | all the populations of different species that live in an ecosystem |
| Consumer | organism that cannot create energy-rich molecules but obtains its food by eating other organisms |
| Ecology | study of the interactions that take place among organisms and their environment |
| Ecosystem | all the living organisms that live in an area and the nonliving features of their environment |
| Habitat | place where an organism lives and that provides the types of food, shelter, moisture, and temperature needed for survival |
| Limiting factor | anything that can restrict the size of a population, including living and nonliving features of an ecosystem, such as predators or drought |
| Mutualism | a type of symbiotic relationship in which both organisms benefit |
| Niche | in an ecosystem, refers to the unique ways an organisms survives, obtains food and shelter, and avoids danger |
| Parasitism | a type of symbiotic relationship in which one organism benefits and the other organism is harmed |
| Population | all the organisms that belong to the same species living in a community |
| Producer | organism, such as a green plant or alga, that uses an outside source of energy like the Sun to create energy-rich food molecules |
| Symbiosis | any close relationship between species, including mutualism, commensalism, and parasitism |
