Ontario Grade 9 Science Class Practice Exam

What is bioamplification/biomagnification?

1. The decrease in substance concentration as it moves down a food web.

2. The stabilization of an ecosystem's population.

3. The increase in concentration of a substance such as a pesticide as it moves up the food web.

4. The magnification of biological sounds in an ecosystem.

The correct answer is: The increase in concentration of a substance such as a pesticide as it moves up the food web.

Bioamplification or biomagnification refers to the process of toxins or pollutants increasing in concentration as it moves up the food chain. This occurs because the organisms at higher levels of the food chain consume larger amounts of the toxin or pollutant through their consumption of lower level organisms. This process can have harmful effects on the organisms at the top of the food chain. Option A is incorrect because it refers to the opposite process, known as biomagnification. In this process, the concentration of substances decreases as it moves down the food web. Option B is incorrect because it refers to the stabilization of an ecosystem's population, which is not related to bioamplification or biomagnification. Option D is incorrect because it refers to the amplification of biological sounds, which is not related to bioamplification or biomagnification.