Multiple choice

DCMU is a herbicide, which can prevent

  1. non cyclic photophosphoylation of light reaction

  2. both non cyclic photophosphoylation and oxygen liberation

  3. inhibits dark reaction

  4. promotes photorespiration
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

DCMU (Diuron) inhibits electron transport from Photosystem II to plastoquinone, which blocks both non-cyclic photophosphorylation (linear electron flow) and oxygen evolution from water splitting. This herbicide specifically targets the photosynthetic electron transport chain. It does not directly inhibit dark reactions or promote photorespiration.

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