1.Virus-mediated transfer of cellular genetic material from one bacterial cell to another

by means of virus particles is called:

(A) transduction

(B) transposition

(C) transformation

(D) transfection

2.  One strand of double-stranded DNA is mutated, changing all cytosines to uracils. After one round of replication of  the mutated DNA strand, the melting temperature of the resulting DNA will:

(A) be higher

(B) be lower

(C) remain the same

(D) be double

3. The Southern blotting technique is used for:

(A) the detection of RNA fragments onmembranes by specific radioactiveantibodies

(B) the detection of DNA fragments onmembranes by a radioactive DNAprobe

(C) the detection of proteins on membranesusing a radioactive DNA probe

(D) the detection of DNA fragments onmembranes by specific radioactiveantibodies

4. Superoxide dismutase is an important enzyme for maintenance of red blood cells and is defective insome neurodegenerative diseases. What does this enzyme do?

(A) catalyzes the conversion of O2- to H2O2 and O2

(B) createssuperoxides by oxidizing heme

(C) converts H2O2 to water and O2

(D) removes H2O2 by oxidizing glutathione and producing water

5. Carboxymethyl cellulose is:

(A) acation -exchange matrix

(B) a gel filtration matrix

 (C) an anion-exchange matrix

(D) a plant cell wall constituent

6. Targetted suppression of gene expression isachieved by:

(A) T-DNA insertion

(B) EMS

(C) RNAi

(D) Gamma ray

7. Cystic fibrosis is due to:

(A) defective chloride channel

(B) defective LDL receptor

(C) High levels of HDL

(D) increased dopamine

8. The main difference between active transport and facilitated diffusion is that:

(A) in active transport, the molecules move from areas of high concentration to areas of low concentration

(B) carrier protein is involved only in case of active transport

(C) in active transport, energy is consumed to move molecules against a concentration gradient

(D) in active transport, only water molecules are transported

9. In competitive inhibition

(A) Km increases, V max constant

(B) Km decreases, Vmax constant

(C) Km constant, Vmax increases

(D) Km decreases, Vmax increases

10. The endogenous GTPase activity of G-proteins serves to:

(A) stimulate the activity of enzymes by producing energy

(B) synthesize cGMP as a second messenger

(C) synthesize GTP as an energy source

(D) hydrolyze GTP returning the G protein to a pre-stimulated level of activity

11. The insulin receptor functions as a:

(A) receptor with 7 transmembrane spanning regions

(B) nuclear protein that acts as a transcription factor

(C) receptorguanylatecyclase

(D) tyrosine kinase

12. Immuno-suppression is mediated by T-cells

having:

(A) CD4+CD25-

(B) CD8+CD25-

(C) CD8+CD25+

(D) CD4+CD25+

13. The germ layer that produces nervoussystem is:

(A) endoderm

(B) mesoderm

(C) ectoderm

(D) endoderm and mesoderm

14. Which of the statements is true for matured human RBC? It

(A) divides once a day

(B) does not divide

(C) divides every 120 days

(D) divides under stressful condition

15. A researcher made an interesting observation about a protein made by the rough ER and eventually used to build a cell's plasma membrane. The protein in the membrane was slightly different from the protein made in the ER. The protein was probably changed in the:

(A) Golgi apparatus.

(B) Smooth ER.

(C) Mitochondrion.

(D) Nucleus

16. Heparin is a:

(A) lipopolysaccharide

(B) glycated lipopolysaccharide

(C) sulphated polysaccharide

(D) sulphated lipopolysaccharide

17. Fertilized single cell cattle egg is what type of stem cell?

(A) Totipotent stem cell

(B) Pluripotent stem cell

(C) Multipotent stem cell

(D) None of the above

18. Agar-agar is a polymer of:

(A) Glucose

(B) Sulphated sugar

(C) Pectin

(D) Protein

19.  Which one of following is an essential fatty acid:

A.    Palmitic acid

B.     Stearic acid

C.     Linolenic acid

D.    Oleic acid

20.  Identify the product (X) in following reaction:

A.    Propionyl CoA

B.     Succinyl CoA

C.     Butryl CoA

D.    Malonyl CoA

21.  Which of the following apolipoprotein is the integral part of chylomicron:

A.    Apo B-48

B.     Apo B-100

C.     Apo A-I

D.    Apo D

22.  The diet of a child suffering from Maple syrup urine disease (an amino acid disorder), should be low, in which out of the following amino acids content?

A.   Branched chain amino acids

B.   Phenylalanine Alanine

C.    Methionine

D.     Tryptophan

23.  Urea is synthesized in -

A.     Cytoplasm

B.     Mitochondria

C.     Both cytoplasm and mitochondria

D.     In lysosomes

24.  Which out of the followings is required as a coenzyme for the transamination reactions?

A.    Coenzyme A

B.    Pyridoxal-P

C.    Folic acid

D.    Cobalamine

25.  All are true with regard to glucagon except:

A.    Increases lipolysis

B.     Favours glycogenolysis

C.     Increases glycogen synthesis

D.    Favours gluconeogenesis

26.  Which of the following will be elevated in the bloodstream about 2 hours after eating a high-fat food?

A.     Chylomicron

B.     High-density lipoprotein

C.      Ketone bodies

D.     Free Fatty acids

27.  Cardiolipin, a phospholipid is present in following organelle:

A.    Lysosome

B.    Endoplasmic reticulum

C.   Mitochondria

D.   Nucleus

28.  Polyunsaturated fatty acids are required for following purposes, except

A.    Synthesis of leukotrienes

B.    Synthesis of prostaglandins

C.   Esterification of cholesterol

D.   Conjugation of bile salt

29.  Which one of the following enzyme is a target for Statins (class of drugs):

A.    HMG-CoA reductase

B.    Lecithin:Cholesterolacyltransferase (LCAT)

C.   Thiolase

D.   HMG-CoA Synthase

30.  Which of the following is a common compound shared by the TCA cycle and the Urea cycle?

A.    α- Ketoglutarate

B.    Succinyl co A

C.   Oxaloacetate

D.   Fumarate

31.  In a 55- year-old man, who has been diagnosed with cirrhosis of liver, Ammonia is not getting detoxified and can damage brain. Which of the following amino acids can covalently bind ammonia, transport and store in a nontoxic form?

A.    Aspartate

B.    Glutamate

C.   Serine

D.   Cysteine

32.  Von-Gierke's disease is characterised by deficiency of

A.    Glucose-6-phosphatase

B.    Glyceraldehyde-3-phosphate dehydrogenase

C.   Phosphofructokinase

D.   Phosphorylase

33.  Which of the following is an additional enzyme required for the beta-oxidation of oleic acid?

A.    D³, D²enoyl-CoA transferase

B.    D³, D²enoyl-CoA hydratase

C.   D³, D²enoyl-CoA isomerase

D.   D³, D²enoyl-CoA dehydrogenase

34.  Which one of the following lipid is NOT the major constituent of plasma membrane :

A.    Phosphatidylcholine

B.    Triacylglycerol

C.   Sphingomyelin

D.   Cholesterol

35.  The antibiotic that resembles the 3' end of the chargedtRNA molecule is

(A) Tetracycline

(B) Puromycin

(C) Kanamycin

(D) Steptomycin.

36. Activation of phospholipase C initiates a sequence ofevents including all of the following, except

(A) release of inositol 4,5-biphosphate from aphospholipid

(B) increase in intracellular Ca2+ concentration

(C) release of diacylglycerol from phospholipid

(D) activation of protein kinase C

37. Full expression of the lac operon requires

(A) lactose and cAMP

(B) allolactose and cAMP

(C) cAMP

(D) lactose

38. An enzyme that induces double strand breaks in DNA and rejoins them is called

(A) Restriction endonuclease

            (B) DNA gyrase

            (C) DNA ligase

            (D) DNA polymerase

39. Which of the following best describes interferon'ssuspected mode of action in producing resistance toviral infection?

(A) It stimulates cell-mediated immunity

(B) It stimulates humoral immunity

(C) Its direct antiviral action is related to thesuppression of messenger RNA formation

(D) Its action is related to the synthesis of a protein thatinhibits translation or transcription

40. The complete denaturation of a protein leads to a loss ofthe following structure(s):

(A) primary

(B) primary and tertiary

(C) primary and secondary

(D) secondary and tertiary     

41. HeLa cell line is derived from which type of carcinoma?

(A) lung

(B) colon

(C) cervical

(D) brain

42. Which one of the following is not an antigen presentingcell?

(A) dendritic Cell

(B) B Cell

(C) macrophage

(D) Natural Killer cell

43. Which of the following leukocytes is present inhighest number in the human blood?

(A) neutrophil

(B) eosinophil

(C) basophil

(D) macrophage         

44. In albino Wistar rats the red colour of the blood is due to

(A) lack of pigmentation

(B) absence of porphyrin ring in the heme of haemoglobin

(C) oxidized state of the iron in the heme

(D) reduced state of the iron in the heme

45. Vitamin E is

(A) menaquinone

(B) α- tocopherol

(C) Phylloquinone

(D) Retinol

46. Cervical cancer is caused by

(A) Papilloma virus

(B) Herpes simplex virus

(C) Hepatitis B virus

(D) Vesicular stomatitis virus

47 Which residue, among alanine, arginine, proline and methionine has the lowest propensity to occur in analpha-helix?

(A) alanine

(B) arginine

(C) proline

(D) methionine

48.Maltose consists of

A.    Glucose + Galactose

B.     Glucose + Fructose

C.     Glucose + Glucose

D.    Glucose + Mannose

49.With regard to biomembrane, all of the following statements are true, except

A.    Carbohydrate residues are located on their surface

B.     They are selectively permeable                                                     

C.     Lipid bilayers contain phospholipids and cholesterol

D.    Their interior is hydrophilic and exterior is hydrophobic

50.Fluidity of biomembrane depends on

A.    Concentration of protein

B.     Type of fatty acids present in phospholipids

C.     Glycosylation of proteins

D.    Membrane pumps