The essential enzyme in C-4 plants used to conserve CO₂ and avoid photophosphorylation is: A) rubisco. B) PEP carboxylase. C) glyceraldehyde-3-phosphate dehydrogenase. D) aldolase. E) ribulose-5-phosphate kinase.

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Quizplus · Accepted Answer

The essential enzyme in C-4 plants used to conserve CO₂ and avoid photophosphorylation is PEP carboxylase. This enzyme is responsible for fixing carbon dioxide into a four-carbon molecule that is then shuttled to a different cell type for further processing. This allows the CO2 to be concentrated, reducing photorespiration and increasing efficiency. Rubisco is also important for carbon fixation, but it is not the key enzyme for conserving CO₂ in C-4 plants. Glyceraldehyde-3-phosphate dehydrogenase, aldolase, and ribulose-5-phosphate kinase are not directly involved in the C-4 pathway.

The Essential Enzyme in C-4 Plants Used to Conserve CO2

The Essential Enzyme in C-4 Plants Used to Conserve CO₂