RuBisCo is an enzyme that acts both as a carboxylase and oxygenase. Why do you think RuBisCo carries out more carboxylation in C4 plants?

Asked by Pragya Singh | 11 months ago |  126

1 Answer

Solution :-

Plants of the C4 family lack the enzyme RuBisCo. Bundle-sheath cells surround vascular bundles rather than contain this protein. As a result, in plants with C4 cells, Calvin cycles do not take place in bundle-sheath cells. CO2 is mainly accepted into cells of the mesophyll by phosphoenol pyruvate, which is a three - carbon compound. In this reaction, it is transformed into oxaloacetic acid (OAA), a four-carbon compound. Further conversion of OAA to malic acid occurs. The Calvin cycle links malic acid to CO2 by decarboxylation in bundle-sheath cells. RuBisCo can no longer function as an oxygenase because of this.

Answered by Abhisek | 11 months ago

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