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Organisms and Populations — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations1 Mark
MCQ
For question two statements are given $-$ one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion : Phytoplanktons grow in abundance in the profundal zone of lake.
Reason : Profundal zone is illuminated by light which supports growth of phytoplanktons.
  • A
    Both assertion and reason are true and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true but reason is not the correct explanation of assertion.
  • C
    Assertion is true but reason is false.
  • ✓
    Both assertion and reason are false.
✓

Answer

Correct option: D.
Both assertion and reason are false.
Life activity underwater is often controlled by the availability oflight. ln aquatic systems the presence of tight determines where producers and consumers are to live in water.
For example, the phytoplanktons $($phyto : plants; plankton : small$)$ live in the illuminated surface layer of water, whereas benthic organisms live in, or at, the segments of a lake. Profundal zone is the dark zone where light does not reach

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