$A$: Holophytic protistans are important phytoplanktons and they contribute $80\%$ of the total photosynthesis.
$R$: They lack chemosynthetic nutrition and utilize non-sulphur organic compounds as the source of electron and proton in carbon assimilation.

  • A
    Assertion and Reason both are correct and Reason is the correct explanation of Assertion.
  • B
    Assertion and Reason both are correct but Reason is not the correct explanation of Assertion.
  • C
    Assertion is correct,but Reason is incorrect.
  • D
    Both Assertion and Reason are incorrect.

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Similar Questions

The accumulation of dead remains of diatoms at the bottom of the ocean is known as ...........

Match the following columns:
Column-$I$ (Protozoans)Column-$II$ (Examples)
$P$. Amoeboid$I$. Plasmodium
$Q$. Flagellated$II$. Amoeba,Entamoeba
$R$. Ciliated$III$. Paramoecium
$S$. Sporozoans$IV$. Trypanosoma

These are simple,predominantly aquatic,unicellular eukaryotes.

Diatomaceous earth is formed due to which substance?

Diatoms stay afloat due to

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