CLASS: M.Sc BIOCHEMISTRY
15N/316
St. JOSEPH’S COLLEGE (AUTONOMOUS) TIRUCHIRAPPALLI – 620 002
SEMESTER EXAMINATIONS – NOVEMBER 2015
TIME: 40 Minutes.
MAXIMUM MARKS: 30
SEM
SET
PAPER CODE
TITLE OF THE PAPER
I
2015
14PBC1103
ENZYMOLOGY AND BIOENERGETICS
SECTION - A
Answer all the questions:
30  1 = 30
Choose the correct answer:
1.
2.
3.
4.
5.
Conjugated enzyme proteins function only in the presence of
specific non-protein molecules or metal ions called ________.
a) Prosthetic group
b) Apoenzyme
c) Holoenzyme
d) Zymogen
_________of an enzyme is the activity per unit weight of enzyme
under certain specified conditions.
a) Specific activity
b) Specificity
c) Katal
d) I.U
__________ is defined as the amount which will catalyze the
transformation of one mole of substance per second.
a) Turnover number
b) Katal
c) Specific activity
d) I.U
Out of total enzymes present in the cell mitochondria alone has
a) 4%
b) 70%
c) 95%
d) no enzymes
Enzymes speed up biochemical reactions by:
a) lowering the activation energy of the reaction
b) increasing the activation energy of the reaction
c) lowering the temperature of the reaction
d) increasing the temperature of the reaction
6.
7.
Which of the following statements is not true regarding the active
site of an enzyme?
a) An active site is normally a hollow or cleft on the surface of an
enzyme.
b) An active site is normally hydrophilic in nature.
c) Substrates fit into active sites and bind to functional groups
within the active site.
d) An active site contains amino acids which are important to the
binding process and the catalytic mechanism
Which of the following is a substrate specific enzyme?
a) Hexokinase
b) Thiokinase
c) Lactase
d) Decarboxylase
8. When the cofactor of an enzyme is a non-protein organic
molecule, it is called a ________.
a) coenzyme
b) cofactor
c) metal ion
d) inhibitor
9. The NAD+ molecule is composed of ________nucleotides bound
together.
a) one
b) two
c) three
d) four
10. The most favored model for the enzyme-substrate interaction is
the ______.
a) Lock and Key
b) Induced fit model
c) Receptor
d) Complementary
11. The enzyme ______ cleaves the bacterial cell wall.
a) Chymotrypsin
b) LDH
c) Lysozyme
d) PDH
12. _______ preferentially cleaves peptide amide bonds where the
carboxyl side of the amide bond
a) Chymotrypsin
b) LDH
c) Lysozyme
d) PDH
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
Most biochemical reactions are ___________ reactions.
a) Bisubstrate
b) Single substrate
c) Null
d) complementary
______becomes an important criterion for distinguishing isoenzymes.
a) Km
b) Vmax
c) Kcat
d) V0
Factors affecting enzyme activity:
a) Concentration
b) pH
c) Temperature
d) All of these
The direct binding of inhibitor to ES complex is ______ inhibition.
a) Competitive
b) Uncompetitive
c) Non competitive
d) Product
Which factor is responsible for inhibition of enzymatic process during
feed back?
a) Enzymes
b) End product
c) Temperature
d) Substrate
Most noncompetitive inhibitors bind to a specific portion of the
enzyme called an ________.
a) allosteric site
b) active site
c) complementary site
d) binding site
_______ are enzymes that differ in amino acid sequence but catalyze
the same chemical reaction.
a) abzyme
b) isoenzyme
c) ribozyme
d) lysozyme
An _______ is an antibody that expresses catalytic activity.
a) abzyme
b) ribozyme
c) lysozyme
d) renin
Increased _____ activities can be used to detect myocardial infarction.
a) Lactate Dehydrogenase
b) Pyruvate Dehydrogenase
c) Lysozyme
d) Chymotrypsin
Most industrial enzymes are obtained from
a) plants
b) microbes
c) insects
d) animal tissues
23. _____ is an analytical device, used for the detection of an analyte that
combines a biological component with a physicochemical detector.
a) PCR
b) Biosensor
c) Centrifuge
d) Photovoltic cell
24. Which one of the following techniques is not ideal for immobilized
cell free enzymes?
a) physical entrapment by encapsulation
b) physical bonding by flocculation
c) covalent chemical bonding by cross linking the precipitate
d) covalent surface bonding to surface carriers
25. ________is defined as the capacity to do work.
a) Enthalpy
b) Energy
c) Entropy
d) Exothermic
26. In biological systems energy is transferred from one molecule to
another via ________ reactions.
a) redox
b) dehydrogenation
c) hydrolytic
d) phosphorylation
27. The extra energy required to destabilize existing chemical bonds and
initiate a chemical reaction is called ________.
a) action potential
b) kinetic energy
c) potential energy
d) activation energy
28. The _______of their phosphate bond makes ATP an excellent energy
donor.
a) instability
b) stability
c) fragility
d) ductility
29. _______ is simply the process by which organisms convert solar
energy to chemical energy
a) Photosynthesis
b) Photophosphorylation
c) Perspiration
d) Thermodynamics
30. The photosystem's stolen electron is replenished by ______.
a) photolysis
b) electrolysis
c) hydrolysis
d) cytolysis
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