Enzymes
Enzymes: Overview
This Topic covers sub-topics such as Enzymes, Activation Energy, Enzyme Inhibition, Coenzyme, Cofactors, Ribozyme, Competitive Inhibition, Noncompetitive Inhibition, Apoenzymes, Enzyme Structure, Prosthetic Group, Nomenclature of Enzymes and, Holoenzymes
Important Questions on Enzymes


Which of the following is correct with respect to the of the enzyme on the equilibrium position?

Given below are two statements :
Statement I : Low temperature preserves the enzyme in a temporarily inactive state whereas high temperature destroys enzymatic activity because proteins are denatured by heat.
Statement II : When the inhibitor closely resembles the substrate in its molecular structure and inhibits the activity of the enzyme, it is known as competitive inhibitor.
In the light of the above statements, choose the correct answer from the options given below :

Malonate inhibits the growth of pathogenic bacteria by inhibiting the activity of:

Which of the following rules states that with the increase of every , the metabolic rate doubles

Select the option which is not correct with respect to enzyme action:


Study the given data and answer the following question.
A sample of an enzyme called lactase was isolated from the intestinal lining of a calf. Assays were undertaken to evaluate the activity of the enzyme sample. The substrate of lactase is the disaccharide lactose. Lactase breaks a lactose molecule in two, producing a glucose molecule and a galactose molecule.
Two assays were carried out.
Assay 1:
Lactose concentration (% w/v) | 15 | 15 | 15 | 15 | 15 | 15 |
Concentration of enzyme sample (% v/v) | 0 | 5 | 10 | 15 | 20 | 25 |
Reaction rate glucose sec-1 mL-1 | 0 | 25 | 50 | 75 | 100 | 125 |
Assay 2:
Lactose concentration (% w/v) | 0 | 5 | 15 | 20 | 25 | 30 |
Concentration of enzyme sample (% v/v) | 5 | 5 | 5 | 5 | 5 | 5 |
Reaction rate glucose sec-1 mL-1 | 0 | 15 | 25 | 35 | 40 | 40 |
Which of the following statements can be concluded from the two assays?

Fruit is green when unripe but becomes beautifully colored when ripe. How does this change occur?

How many of the following list are not the polymers of amino acids?
RuBisCO, Hind III, pBR322, Porins, Ribozymes, Lecithin, Serine, DNAse



During enzymatic reactions, enzyme-substrate complex is:

Read the following statements:
A. Living state and metabolism are synonymous.
B. All enzymes are proteins without any exception.
C. Zn acts as a cofactor for the enzyme carbonic anhydrase.
D. At high temperatures inorganic catalysts work efficiently while the enzymes are damaged.
Correct statements are:

Above , what will be the appropriate effect on enzymes and inorganic catalysts?

What will happen, if cofactor is removed from a holoenzyme?


Enzymes catalysing the linking together of two compounds, for example, enzymes which catalyse the joining of etc., bonds belongs to the class of

Enzymes which catalyse the transfer of group other than hydrogen belongs to the class
