All India Institute of Medical Sciences 2003 - Question Paper

3. The substrate concentration at half maximum velocity.
4. Numerically indentical for all isozymes that catalyze a provided reaction.
Ans 1

73. At the physiological pH the DNA molecules are :
1. Positively charged.
2. Negatively charged.
3. Neutral.
4. Amphipathic.
Ans two (harper, this ques. has been in last 2-3 exams)

74. Cholesterol current in LDL :
1. Represents primarily cholesterol that is being removed from peripheral cells.
2. Binds to a receptor and diffuses across the cell membrance.
3. On acuumulation in the cell inhibits replenishment of LDL receptors.
4. When enters a cell, suppresses activity of acyl-CoA: cholesterol acytranferase ACAT.
Ans 3

75 A newborn infant refuses breast milk since the second day of birth, vomits on force-feeding but accepts glucose-water, develops diarrhea on the 3rd day, by fifth day she is jaundiced with liver enlargement and eyes show signs of cataract. Urinary reducing sugar was positive but blood glucose estimated by glucose oxidation method was obtained low. The most likely reason is deficiency of :
1. Galactose-1-phosphate uridyl transferase.
2. Beta galactosidase.
3. Glucose-6-phosphatase.
4. Galactokinase.
Ans 4

76 An obese lady aged 45 years, was brought to emergency in a semi comatose condition. The laboratory investigations showed K+ (5.8 mmol/L); Na+ (136 mmol/L); blood pH (7.1), HCO3 (12 mmol/L),' ketone bodies (350 mg/dl). The expected level of blood glucose for this lady is:
1. < 45 mg/dl.
2. < 120 mg/dl.
3. >180 mg/dl.
4. < 75 mg/dl.
Ans 2?/ 3? Pseudohypernatremia / Diabetic ketoacidosis (to be updated any points?)

77. Replication and transcription are similar processes in mechanistic terms because both :
1. Use RNA primers for initiation.
2. Use decoxybonucleotides as precursors.
3. Are semi conserved events
4. Involve phosphodiester bond formation with elongation occurring in the 5' - 3' direction.
Ans 2

78. Commonest reason of neonatal mortality in India is :
1. Diarrheal diseases.
2. Birth injuries.
3. Low birth weight
4. Congenital anomalies.
Ans 3

79. All of the subsequent features are suggestive of asbestosis except:
1. Occurs within 5 years of exposure.
2. The disease progresses even after removal of contact.

Earning:   Approval pending.