Question Bank No: 1

1. Which one of the following us resistant to enzyme action?

 a)Leaf cuticle
 b)Cork
 c)Wood fibre
 d)Pollen exine

2. Ribozyme is

 a)RNA withour phosphate
 b)RNA with sugar
 c)RNA with exzyme activity
 d)RNA with extra phosphate

3. Many enzymes are secreted in inactive form to protect

 a)Cell membrane
 b)Mitochondria
 c)Cell proteins
 d)Cell DNA

4. The first enzyme to be purified and crystallized was

 a)Urease
 b)Diastase
 c)Insulin
 d)Zymase

5. In which of the following organisms enzymes are absent

 a)Fungi
 b)Viruses
 c)Algae
 d)Bacteria

6. Value needed for enzyme action is ______

 a)Low Km
 b)Low Ki
 c)High KM
 d)High Ki

7. An example of competitive inhibition of an enzyme is the inhibition of

 a)Succinic dehydrogenase by malonic acid
 b)Cytochrome oxidase by cyanide
 c)hexokinase by glucose-6- phosphate
 d)carbonic anhydrase by carbon dioxide

8. The coenzyme is

 a)often a meta
 b)always a protein
 c)often a vitamin
 d)always an inorganic compund

9. In which one of the following sets of three items each belong to the category mentioned against them?

 a)Lysine, glycine, thiamine - Amino acids
 b)Myosin, oxytocin and gastric - Hormones
 c)Rennin, helicase and hyaluronodase - Enzymnes
 d)Optic nerve, oculomotor, vagus - Sensory nerves

10. Enzymes, vitamins and hormones can be classified into a single category of biologival chemicals because all of these

 a)Are exclusively synthesized in the body of a living organism as at present
 b)Enhance oxidative metabolism
 c)Are conjugated proteins
 d)Help in regulating metabolism

11. Which of the following statements regarding enzyme inhibition is correct?

 a)Competitive inhibition is seen when a subtrate competes with an enzyme for binding to an inhibitor protein
 b)Non-competitive inhibitators often bind to the enzyme irreversibly
 c)Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the enzyme
 d)Non- Competitive inhibition of an enzyme can be overcome by adding large amount of substrate

12. Which one is the most abundant protein in the animal world?

 a)Collagen
 b)Insulin
 c)Trypsin
 d)Haemoglobin

13. The "Repeating Unit" of glycogen is

 a)Fructose
 b)Mannose
 c)Glucose
 d)Galactose

14. Enzymes that catalyse inter-conversion of optical, geometrical or positional isomers are

 a)Ligases
 b)Lyases
 c)Hydrolases
 d)Isomerases

15. The eggectiveness of an enzyme is affected least by

 a)Temperature
 b)Concentration of the substrate
 c)Original activation energy of the systems
 d)Concentration of the enzyme

16. Example of a typical homopolysaccharide is

 a)Lignin
 b)Suberin
 c)Inulin
 d)Starch

17. Feedback inhibition of enzymes is effected by which of the following

 a)enzyme
 b)substrate
 c)end products
 d)intermediate end products

18. One strand of DNA has the following sequence of nucleotide 3' ATTCGCTAT 5', so the other strand of DNA has

 a)5' TAAGCGATA 3'
 b)3' TAAGCGATA 5'
 c)5' GACGCGATA 3'
 d)3' GACGCGATA 5'

19. The "lock and key" model of enzyme action illustrates that a particular enzyme molecule

 a)May be destroyed and resynthesised several times
 b)Interacts with a specific type of substrate molecule
 c)Reacts at identical rates under all conditions
 d)Forms a permanent enzyme- substrate comples