NCERT Class 11-Biology: Chapter – 13 Photosynthesis in Higher Plants Part 9 (For CBSE, ICSE, IAS, NET, NRA 2023)

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Question 11:

Name the two important enzymes of and pathway, respectively? What important role do they play in fixing ?


Rubisco and PEP case are the two important enzymes of and pathways. Rubisco is the primary receiver in facilities while PEP case is the main receiver for facilities.

Rubisco՚s role: The Rubisco RUBP carboxylase is also called oxygenase. It has carboxylase as well as oxygenase functions, as the name suggests. The enzyme has more carbon dioxide potential than oxygen affinity. Some of the enzyme, however, is linked to oxygen

plants a photorespiration process. Photo vacuum is a wasteful process because it does not produce a product that is useful for plants. In addition, carbon fastening in plants is also reduced.

PEP case Role: this is the primary accepter of carbon dioxide in plants. In these plants, however, Rubisco is also available. carbon Oxaloacetic (OAA) compound PEP case binds to carbon dioxide eventually becomes carbon dioxide.

Carbon dioxide is lastly produced in the cycle of Calvin. Keep in mind that both and plants use the Calvin Cycle.

Question 12:

Why is RuBisCo enzyme the most abundant enzyme in the world?


Rubisco catalyses the first step during the Calvin cycle to transform carbon dioxide into sugar. In all photosynthetic organisms worldwide, this enzyme is present. From cyanobacteria to the floors of large trees; literally, Rubisco is present all over the place.

All carbon in the biosphere can be said to be derived from Rubisco carbon fixation. This is therefore the world՚s largest enzyme.

Question 13:

Why does not photorespiration take place in plants?


Plants over plants have a definite benefit from the bundled sheath. The sheath contributes to increased concentration of carbon dioxide in the leaves. We are aware of the competition between Rubisco and carbon dioxide and oxygen. We also know that the relative carbon dioxide and oxygen concentration affects the binding of this enzyme to a specific molecule. The high carbon dioxide concentration in the plants makes all Rubisco bind to carbon dioxide, and no oxygen binding exists.

In these plants, therefore, photorespiration does not occur.