NEETBotanyEcosystem
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The pyramid of biomass in a sea is generally inverted. Reason (R): The biomass of fishes far exceeds that of phytoplankton. In the light of the above statements, choose the correct answer from the options given below:
Options
- ABoth Assertion and Reason are true but Reason is not the correct explanation of Assertion.
- BBoth Assertion and Reason are true and Reason is the correct explanation of Assertion.
- CAssertion is true but Reason is false.
- DAssertion is false but Reason is true.
Correct answer
B. Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
Step-by-step solution
Assertion is true. In aquatic ecosystems such as a sea or pond, the pyramid of biomass is generally inverted. Reason is also true and correctly explains the Assertion. The pyramid is inverted because the standing crop of phytoplankton (producers) is much lower than the standing crop of fishes (consumers) that depend on them. Phytoplankton have a very high turnover rate (rapid reproduction and short lifespan), allowing a small biomass to support a much larger biomass of fishes. Answer: Both Assertion and Reason are