Final answer:
DDT is a chemical agent that biomagnifies through the food chain. Small organisms accumulate DDT from plants, and larger organisms that eat those smaller organisms accumulate an even higher concentration. This process continues, leading to higher levels of DDT in organisms at the top of the food chain.
Step-by-step explanation:
The pesticide DDT is a chemical agent that can biomagnify through the food chain. When DDT is used, it enters the environment and is absorbed by plants. Small organisms, such as insects, eat the plants and accumulate DDT in their bodies. Then, larger organisms that eat those smaller organisms, like birds or fish, accumulate an even higher concentration of DDT in their bodies. This process continues as organisms at each trophic level consume those below them, leading to higher levels of DDT in organisms at the top of the food chain, like eagles and pelicans.