6. During sickle cell anemia which of the following takes place?

A. Glutamine change to valine
B. Valine change to glutamine
C. Aspartic acid change to glutamic acid
D. Glutamic acid change to aspartic acid

7. Methotrexate is toxic to human cells because it inhibits

A. formation of CTP from UTP
B. reduction of H2 folate to H4 folate
C. synthesis of PRPP
D. none of the above

8. What is the defective enzyme in glycogen storage Von Gierke’s disease?

A. Phosphorylase
B. Phosphofructokinase
C. Glucose-6-phosphatase
D. None of the above

9. A deficiency of the enzyme Hypoxanthine Guanine phosphoribosyl transferase (HGPRT) may cause

A. Gaucher’s disease
B. Ehlers-Danlos syndrome
C. Lesch- Nyhan syndrome
D. Klinefelter’s syndrome

10. Which of the following sets belongs to a distinct class or category?

A. Ribose, sucrose, glucose, fructose
B. Sterols, waxes, fatty acids, amino acids.
C. Oils, sterols, waxes, fats
D. Nucleotide, nucleoside, nucleus, DNA