| A | B | 
|---|
| ecology | the study of the interactions between organisms & their environment | 
| biotic | describes living factors in the environment | 
| abiotic | describes nonliving factors in the environment | 
| population | a group of individuals of the same species that live together in the same area at the same time | 
| community | all of the populations of different species that live and interact in an area | 
| ecosystem | a community of organisms & its abiotic environment | 
| biosphere | the part of the Earth where life exists | 
| organism | a living being | 
| herbivore | a consumer that eats plants | 
| carnivore | a consumer that eats animals (meat) | 
| omnivore | a consumer that eats both plants & animals | 
| scavenger | an animal that feeds on the bodies of dead animals | 
| food chain | a diagram that shows how the energy in food molecules flows from 1 organism to the next | 
| decomposer | an organism that gets energy by breaking down the remains of dead organisms or animal wastes & consuming or absorbing the nutrients | 
| food web | a diagram that shows the many energy pathways in a real ecosystem | 
| habitat | the environment where an organism lives | 
| niche | an organism's way of life & its relationship with its abiotic and biotic environments | 
| energy pyramid | a diagram shaped like a triangle that shows the loss of energy at each level of the food chain |