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1

The first step in fatty acid synthesis involves
(A) Acetyl CoA carboxylase
(B) 3 Hydroxyl CoA dehydrogenase
(C) Acetyl dehydrogenase
(D) Pyruvate kinase

(A) Acetyl CoA carboxylase

2

Enzymes that move a molecular group from one molecule to another are known as -
(A) Ligases
(B) Oxido-reductases
(C) Transferases
(D) Dipeptidases

(C) Transferases

3

Mechanism by which pyruvate cytosol is transported to mitochondria is -
(A) Chloride antiport
(B) Proton symport
(C) ATP dependent antiport
(D) Facilitated uniport

(B) Proton symport

4

Which of the following statement about thiamine is true?
(A) It is a co-enzyme of lactate dehydrogenase
(B) Its deficiency is associated with scurvy'
(C) Its co-enzyme function is done by thiamine monophosphate
(D) It is co-enzyme for pyruvate dehydrogenase and on-ketoglutarate dehydrogenase

(D) It is co-enzyme for pyruvate dehydrogenase and on-ketoglutarate dehydrogenase

5

In Beriberi, which enzyme activity is measured?
(A) Transketolase
(B) Transaminase
(C) Decarboxylase
(D) Deaminase

(A) Transketolase

6

Creatinine is formed from:
(A) Arginine
(B) Lysine
(C) Leucine
(D) Histamine

(A) Arginine

7

Serine proteases:
(A) Hydrolyze peptide bonds involving carboxyl groups of serine residues
(B) Are characterized by having several active sites per molecule each containing a serine residue
(C) Are inactivated by reaching with one molecule of di-isopropyl-fluorophosphate per molecule of protein
(D) Are Exopeptidase

(B) Are characterized by having several active sites per molecule each containing a serine residue

8

The parameter used as an index of lipid peroxidation is the level of:
(A) Ascorbic acid
(B) Hydrogen peroxide
(C) Malondialdehyde
(D) Volatile fatty acids

(C) Malondialdehyde

9

Features of Vitamin C deficiency is due to defect of which enzyme?
(A) Lysyl hydroxylase
(B) Lysyl oxidase
(C) Procollagen
(D) Peptidase

(A) Lysyl hydroxylase

10

All the following degradation product of Glycine, except:
(A) Serine
(B) Oxalates
(C) Pyruvates
(D) Ornithine

(D) Ornithine

11

In competitive inhibition the relation Km and Vmax is one of the following:
(A) Km and Vmax are the same
(B) Km increases and Vmax is the same
(C) Km decreases and Vmax increases
(D) Km and Vmax decreases

(B) Km increases and Vmax is the same

12

Enzyme deficient in Marfan's syndrome:
(A) Cystathionine beta synthase
(B) Elastase type II
(C) Lysyl oxidase
(D) Collagenase
(E) None of the above

(E) None of the above

*Cystathionine beta synthase

It catalyzes the first step of the transsulfuration pathway, from homocysteine to cystathionine:

13

Porphyrias absorb light in the wavelength of:
(A) 340nm
(B) 400nm
(C) 540nm
(D) 67Onm

(B) 400nm

14

All of the following is/are extracellular matrix protein, except?
(A) Collagen
(B) Laminin
(C) Fibronectin
(D) Integrin
(E) Elastin

(D) Integrin

15

What is the most acute effect of smoking cessation?
(A) Shift of oxyhemoglobin curve to the right
(B) Increased ciliary function
(C) Decreased mucous production
(D) Decreased incidence of post operative pneumonia

(A) Shift of oxyhemoglobin curve to the right

16

Enzymes not important in testosterone biosynthesis:
(A) 5-alpha reductase
(B) Delta 5-4 isomerase
(C) 18 hydroxylase
(D) Alpha hydroxylase

(C) 18 hydroxylase

17

The rate limiting enzyme in glycolysis:
(A) Glucose 6-dehydrogenase
(B) Phosphofructokinase 1
(C) Glucokinase
(D) Pyruvate kinase I

(B) Phosphofructokinase 1

18

At isoelectric pH protein:
(A) Have Net charge 0
(B) Are positively charged
(C) Are negatively charged

(A) Have Net charge 0

19

Heart uses one of following as energy source during starvation:
(A) Glucose
(B) Acetoacetate
(C) Fats
(D) Proteins

C) Fats

20

Vitamin C is present in largest amount in the body in:
(A) Eye
(B) Kidneys
(C) Testes
(D) Adrenal cortex
(E) Pancreas

(D) Adrenal cortex

21

Ehrlich's test is done to detect:
(A) Urinary amylase
(B) Urinary cystine
(C) Abnormal porphyrin
(D) Urobilinogen

(D) Urobilinogen

22

What is the connecting link between urea cycle and TCA cycle?
(A) Fumarate
(B) Succinate
(C) Oxaloacetate
(D) Arginine succinate

(A) Fumarate

23

Excessive ultraviolet (UV) radiation is harmful to life. The damage caused to the biological systems by ultraviolet radiation is by:
(A) Inhibition of DNA synthesis
(B) Formation of thymidine dimers
(C) Ionization
(D) DNA fragmentation

(B) Formation of thymidine dimers

24

Squalene" is the intermediate product during synthesis of:
(A) VLDL
(B) Cholesterol
(C) Tachysterol
(D) Lanosterol

(B) Cholesterol

25

Which of the following statements about facilitated diffusion is true?
(A) It is a form of active transport
(B) It requires a carrier protein
(C) Rate of transport is proportionate to the concentration gradient
(D) Requires creatine phosphate

(B) It requires a carrier protein

26

Respiratory distress syndrome in premature infants is due to inadequate secretion of which one of the following lipids?
(A) Dipalmitoyl phosphatidylcholine
(B) Sphingomyelin
(C) Cholesterol
(D) Phosphatidylinositol

(A) Dipalmitoyl phosphatidylcholine

27

Apart from occurring in nucleic acids pyrimidines are also found in:
(A) Theophylline
(B) Theobromine
(C) Flavin mononucleotide
(D) Thiamine

(D) Thiamine

28

During standard plasma electrophoresis a protein that moves ahead of albumin is:
(A) Fibrinogen
(B) Alpha feto protein
(C) Hemopexin
(D) Retinol binding protein

(D) Retinol binding protein

29

Glycosphingolipid is made up of the following, except:
(A) Glucose
(B) Glycerol
(C) Sphingosine
(D) Fatty acids

(B) Glycerol

30

Andersen disease is due to deficiency of:
(A) Debranching enzyme
(B) Branching enzyme
(C) Myophosphorylase
(D) Acid maltase

(B) Branching enzyme