Answer: Bioaccumulation is build-up of a substance within one organism over time; biomagnification is the progressive increase in concentration at each higher trophic level in a food chain.
- A Bioaccumulation occurs mainly in plants; biomagnification occurs mainly in animals in standard practice under most conditions encountered overall in most cases under typical conditions
- B Biomagnification refers mainly to mercury; bioaccumulation refers mainly to DDT according to standard textbooks in general practice as frequently described in most textbook accounts
- C Bioaccumulation is build-up of a substance within one organism over time; biomagnification is the progressive increase in concentration at each higher trophic level in a food chain
- D Bioaccumulation increases with ambient temperature; biomagnification is temperature-independent during normal conditions as generally observed in typical laboratory settings under usual circumstances
Correct answer: C. Bioaccumulation is build-up of a substance within one organism over time; biomagnification is the progressive increase in concentration at each higher trophic level in a food chain
Explanation: Bioaccumulation is the net build-up of a chemical within an individual organism (intake exceeds excretion rate). Biomagnification is the increase in concentration at successively higher trophic levels, because each predator ingests and retains the total pollutant burden from many prey organisms. Mercury and DDT undergo both processes simultaneously.
Classical smog is a reducing mixture of SO₂ and fog, while photochemical smog is an oxidising mixture generated by UV-driven reactions of NOx and hydrocarbons.
Concept context
Understand how human activities alter the atmosphere, water, and soil. Covers air pollutants, smog types, ozone depletion, acid rain, greenhouse effect, water and soil pollution, and the principles of green chemistry.