Question

Assertion : Presence of large amounts of nutrients in water body causes excessive growth of planktonic algae.
Reason : It is due to biomagnification.

• A. If both assertion and reason are true and reason is the correct explanation of assertion
• B. If both assertion and reason are true but reason is not the correct explanation of assertion
• C. If assertion is true but reason is false
• D. If both assertion and reason are false

Answer 1

Answer: (C)

Presence of large amounts of nutrients in water causes excessive growth of planktonic (free-floating) algae, called an algal bloom which imparts a distinct colour to the water bodies. Algal blooms cause deterioration of the water quality and fish mortality. Biomagnification refers to increase in concentration of the toxicant at successive trophic levels.