| A | B |
|---|
| calorie | a unit of measure for the energy value of food |
| joule | a unit of energy (J) |
| energy transfer | the movement of energy from one level of a food chain to another |
| food chain | a simple chain of feeding relationships between 3 or 4 organisms |
| food web | complex network of feeding relationships between a large number of organisms |
| producer | an organism that uses energy from the sun to make food by photosynthesis; usually a plant |
| consumer | an organism that cannot make its own food; it needs to eat ready-made food in the form of plants or other animals |
| primary consumer | an organism that eats only plants |
| secondary consumer | an organism that eats an animal that is a primary consumer |
| tertiary consumer | an organism that eats a secondary consumer; tertiary consumers are usually at the top of the food chain |
