Enzyme Biology Test 01

Total Questions: 22

1 - What is TRUE about enzymes?

A ) They make biochemical reactions to produced spontaneously
B ) They lower the activation energy of a reaction ✅
C ) They are not very specific in their choice of substances
D ) They are needed in large quantities

2 - To what category of molecules do enzymes belong? / Chemically enzymes are;

A ) Carbohydrates
B ) Lipids
C ) Nucleic acids
D ) Proteins ✅

3 - What is true about cofactors?

A ) Break hydrogen bonds in proteins
B ) Help facilitate enzyme activity ✅
C ) Increase activation energy
D ) Are composed of proteins

4 - Prosthetic groups are;

A ) Required by all enzymes
B ) Loosely attached with enzymes
C ) Proteins in nature
D ) Tightly bound to enzyme ✅

5 - When we add more substrate to an already occurring enzymatic reaction and there is no increase in the rate of reaction, what would you predict?

A ) All active sites have been occupied by substrate molecules ✅
B ) They enzyme molecules have denatured
C ) More substrate acted as inhibitor
D ) More substrate has disturbed the pH of the medium

6 - The substance on which an enzyme acts is called:

A ) Cofactor
B ) Inhibitor
C ) Coenzyme
D ) Substrate ✅

7 - NoN- protein part of enzymes are:

A ) Inhibitors
B ) Substrate
C ) Cofactors ✅
D ) Coenzymes

8 - Optimum temperature for enzymes of human body is:

A ) 86°C
B ) 37°C ✅
C ) 38°C
D ) 39°C

9 - Activation energy is required to:

A ) Activate enzymes
B ) Start a reaction ✅
C ) Speed up a reaction
D ) None of these

10 - Lock and key model was proposed by:

A ) Emil fischer ✅
B ) Menscher
C ) Koshland
D ) Saugeo

11 - Induced Fit model was proposed by:

A ) Emil Fischer
B ) Koshland ✅
C ) Meischer
D ) Schleiden

12 - Enzyme which break the peptide bonds:

A ) Amylase
B ) Protease ✅
C ) Lipase
D ) Pepsin

13 - Which enzyme converts lipids into fatty acid and glycerol?

A ) Lipase ✅
B ) Amylase
C ) Pepsin
D ) Trypsin

14 - Number of discovered enzymes more than;

A ) 200
B ) 2000 ✅
C ) 3000
D ) 3500

16 - The active site of an enzyme;

A ) Never changes
B ) Forms no chemical bond with substrate
C ) Determines by its structure the specificity of the enzyme. ✅
D ) Looks like a lump projecting from the surface of an enzyme.

17 - Enzymes have all the characters EXCEPT:

A ) They consist of proteins with or without a non-protein part
B ) They charge the rate of catalyzed reaction
C ) They have sensitive to heat
D ) They are non-specific in their action ✅

18 - The covalently bonded co-factors are:

A ) Activators
B ) Prosthetic group ✅
C ) Co-enzyme
D ) Prosthetic group and coenzyme

19 - Reaction can take place without enzyme but;

A ) Reaction will be more fast
B ) At the same speed as that with enzyme
C ) More product will be formed
D ) Speed of the reaction will be slow

20 - Active site;

A ) Is the small catalytic region of enzyme molecule ✅
B ) Is non-charge bearing site
C ) Is non-catalytic region of enzyme molecule
D ) Is not a part of an enzyme

21 - Enzyme always react with a specific substrate because of;

A ) Specific shape and specific amino acids ✅
B ) Specific prosthetic group
C ) Capability to form specific bonds
D ) Specific coenzyme

22 - Emil Fischer proposed the Lock and key Model in:

A ) 1890
B ) 1800
C ) 1894 ✅
D ) 1900