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Home /
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MDCAT Past Papers /
DUHS /
Biology /
Chap No 3 /
Quiz 1

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MDCAT Past Papers - DUHS - Biology - Chap No 3 Quiz

Attempt 10 MCQs on MDCAT Past Papers - DUHS - Biology - Chap No 3 | Quiz 1

1. If the co-factor is tightly, permanently and covalently bonded to enzyme then it is called:

Co enzyme
Activator
Prosthetic group
Apo enzyme

2. The view that active site of enzyme is flexible and when a substrate combines with it, it causes change in enzyme structure is known as:

Lock and Key model
Induced Fit model
Sliding filament model
Specificity model

3. Zinc ion is attached at the active site of the enzyme carboxypeptidase. The zinc ion functions as:

Co-enzyme molecule
An activator
Controller of allosteric site
An inhibitor

4. The catalytic activity of an enzyme is restricted to its small portion

Active site
Passive site
Regulation site
Allosteric site

5. Lock and key model for enzyme action proposed by Emil fischer suggests that:

Enzymes are unbiased for the substrate
Enzymes can modify their active sites
Enzymes are restricted to one reaction type
Enzyme can catalyze variety of reactions

6. Select a regulatory enzyme:

Urease
Hexokinase
Maltase
Sucrase

7. All of the following are the postulates of lock and key model, EXCEPT?

Active site has a rigid structure
Enzymes are non regulatory
One specific key can only open specific lock
Substrates combines with an enzyme to induces change in enzyme structure

8. Enzymes are __________ in nature

Proteins
Lipds
Carbohydrates
Vitamins

9. What alters the shape of enzymes and makes them functional?

Co-factor
Proteins
Other enzymes
A and C

10. Which of the following is true about ATP?

Coenzyme
Prosthetic group
Enzyme
organic ion of enzyme

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