By the end of the 12th grade, students should be able to describe the effects of biological magnification on ecosystems. This lesson will focus on biomagnification as it relates to the ecosystems of the Great Lakes region in the mid-western United States.
Photosynthetic plankton are microorganisms that turn solar energy into nutrients.
These tiny creatures are consumed by zooplankton and fish. Explain to students that potentially toxic chemicals released or created by human activity often get into surface waters and, from there, into the food chain. When microorganisms ingest chemicals, those chemicals can be magnified further up the food chain. This may happen as fish ingest plankton that have higher than average levels of a toxin. As larger fish consume smaller fish, the concentration of toxins in animal tissues may increase.