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Biomolecules — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryBiomolecules5 Marks
Question
Define enzymes. How do enzymes differ from ordinary chemical catalysts?
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Answer

Ans. Enzymes are naturally occurring simple or conjugate proteins acting as specific catalysts in cell processes. The enzyme facilitates a biochemical reaction by providing alternative lower activation energy pathways thereby increasing the rate of reaction.

Enzymes are different from ordinary chemical catalysts in following ways:

  1. They are highly specific in their action, i.e., each enzyme can catalyse only a specific type of reaction.
  2. Enzymes can speed up reactions to the extent of about ten million times.
  3. Enzymes function at a moderate temperature (about 310K) and moderate pH (6-8).
  4. Even a small quantity of an enzyme can catalyse the reaction of a large quantity of the substrate. This is because in chemical reactions the catalyst (enzyme) is regenerated after the reaction.

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