All India Institute of Medical Sciences 2009 BIOCHEMISTRY - Question Paper

BIOCHEMISTRY

Q1. After cutting DNA with restriction enzymes; segments are joined by:
a- Endonuclease-
b- Ligase
c- Topoisomerase
d- Helicase
Ans: b.

Q2. Intestinal flora digests all except:
a- Cellulose
b- Lignin
c- Pectin
d- Starch
Ans: d.

Q3. Acetyl CoA can be directly converted to all except:
a- Fatty acid
b- Glucose
c- Ketone bodies
d- Cholesterol
Ans: b.

Q4. Splicing is associated with:
a- mRNA
b- Sn RNA
c- r RNA
d- t RNA
Ans: b.

Q5. LPL incorrect is:
a- Is obtained in adipose tissue
b- Is obtained in myocytes
c- Def leads to hyper TG
d- Does not require C-II as cofactor
Ans: d.

Q6. A male child presents with delayed development and biting of the lips and hands. His parent have restrained him because he obsessively chews on his lips and fingers which of the subsequent is likely to occur in this child?
a- HGPRTase def
b- Adenosine deaminase def
c- Phenylalanine hydroxylase def
d- Sphingomyelinase def
e- None
Ans: a.

Q7. CAP in Lac Operon is an example of:
a- Positive regulator
b- Negative regulator
c- Constitutive expression
d- Attenuation
Ans: a.

Q8. Oxidation reduction reaction occurs with all except:
a- Hydroperoxidases
b- Peroxidases
c- Oxygenases
d- Dehydrogenases
Ans: a.

Q9. MICRO RNA function:
a- Gene regulation
b- DNA conformation
c- RNA splicing
d- Translation
Ans: a.

Q10. Best marker for stratification of Cardiovascular disease risk:
a- Homocystine
b- Lipoprotein (a)
c- Anti-chlamydial antibody
d- CRP
Ans: b.

Q11. lowest polar among subsequent groups:
a- Methyl
b- Amino
c- Carboxyl
d- Phosphate
Ans: a.

Q12. subsequent SDS-PAGE electrophoresis, protein with is obtained to be 100 KD. After Rx with mercaptoethanol, it indicates two bands of 20 KD and 30KD widely separated. actual statement:
a- Protein has undergone hydrolysis of S-S linkage
b- It’s dimer of two subunits of 20 and 30 KD
c- It’s a tetramer of two 20 KD and two 30 KD
d- Protein breakdown due to non-covalent linkage
Ans: a.

Q13. Basic defect in HbS is:
a- Altered function
b- Altered solubility
c- Altered stability
d- Altered O2 binding capacity
Ans: b.

Q14. Characteristic of HbS is all except:
a- change of glutamine to Valine
b- Heterozygotes are protected against malaria
c- Increase in sticky patch due to substitution of nonpolar residue
d- Single base substitution lead to RFLP
Ans: c.

Earning:   Approval pending.