What does biomagnification refer to?

Biomagnification refers to the process where the concentration of toxins increases in organisms as one moves up the food chain. This happens because predators consume prey that have ingested toxins, leading to a greater accumulation of these harmful substances in their own bodies. For instance, if a small fish (which has a low level of a toxin) is eaten by a larger fish, the larger fish will accumulate a higher concentration of that toxin because it consumes multiple smaller fish. As this continues with each successive level—moving from smaller organisms to larger predators—the concentration of the toxin can become significantly amplified, potentially leading to adverse health effects in top predators, including humans.

The other choices do not accurately reflect the concept of biomagnification. The spread of diseases pertains to epidemiology rather than environmental toxicology. The absorption of nutrients in plants relates to their physiological processes and does not involve toxins or food chains. The decrease in biodiversity does not specifically address the accumulation of toxins in organisms but rather refers to the loss of various species from an ecosystem.