Clinical Enzymology- MLS476
First Term Exam (1432/1433
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Question-1: Choose the best answer (6 Marks):
1- Clinical enzymology is a branch of science that can be used in
………………..
a) Diagnosis of diseases
b) Treatment of diseases
c) a & b
d) None
2- Enzyme active site consists of ………………..
a) Binding site
b) Catalytic site
c) Allosteric site
d) a & b
3- Enzymes that catalyze same reaction but differ in protein structure
and kinetic parameters are called ………………..
a) Vitamins
b) Isoenzymes
c) Coenzymes
d) Cofactors
4- Liver tissue damage due to acute hepatitis disease leads to
………………..
a) Decrease in oxygen supply and increase in LDH activity
b) Decrease in oxygen supply and unchanged LDH activity
c) Increase in oxygen supply and decrease in LDH activity
d) Unchanged in oxygen supply and decrease in LDH activity
5- Allosteric enzymes shows the following characteristics
………………..
a) Has a sigmoid plot of velocity vs. substrate concentration
b) Has hyperbolic plot of velocity vs. substrate concentration
c) Has only one conformation
d) a & c
6- In comparison between glucokinase and hexokinase, it known that
………………..
a) Glucokinase has a greater Km for glucose than hexokinase
b) Glucokinase has a smaller Km for glucose than hexokinase
c) Both have the same Km for glucose
d) None of the above
Question-2: Answer the following (14 Marks):
I-Write the Lineweaver-Burk equation and draw how it can be used to
determine Km and Vmax. (3 Marks)
Answer:
II-Describe the effect of different types of inhibitors (competitive,
uncompetitive, non-competitive) on Km and values. (3 Marks)
Answer:
Vmax
Km
Unchanged
Increased
competitive
Decreased
Decreased
uncompetitive
Decreased
Unchanged
noncompetitive