BIOCHEMISTRY AND CLINICAL PATHOLOGY || 50 mcq questions with answer || OSSSC || OSSC|| for Any private job AND GOVT. JOB
1. Thyroid-stimulating hormone is secreted by :
(a) Anterior pituitarY
(b) Posterior pituitary
(c)Hypothalamus
(d) Pancreas
2.
The structure of prolactin is:
(a) sterodial
(c) Polypeptide
(b) Peptide
(d) Glycoprotein
3.
Pigmentation of the skin is caused by :
(a) TSH
(c) MSH
(b) LH
(d) Prolactin
4.
Melanocyte stimulating hormone is secreted by :
(a) Anterior lobe of pituitary
(b) Intermediate lobe of pituitary
(c) Posterior lobe of pituitary
(d) Adrenal cortex
5
Anterior lobe of pituitary secretes :
(a) 5 hormones
(b) 6 hormones
(c)7 hormones
(d) none
6.
Insulin is secreted by :
(a) -cells of pancreas
(b)a-cells of pancrease
(c) Liver
(d) Intestine
Mineralocorticoid is secreted by :
(a) Adrenal cortex
(b) Adrenal medulla
(c)Zona glomerulosa (
d) Zona fasciculata
8. Deficiency of thyroid hormone produces :
(a) Cretinism
(b) Myxedema
(c). Goitre
(d) All of the above
9.
Vasopressin is secreted by :
(a) Anterior lobe of pituitary
(b) Intermediate lobe
(c) Posterior lobe
(d) None of the above
10
Human chronic gonadotrophin (HG) hormone is secreted by
(a) Placenta
(b) Ovaries
(c) Tests
(d) None
11.
Riboflavin is a constituent of
(a) Co-carboxylase
(b) Co-decarboxylase
(c) NAD+
(d) FAD
(e) PRPP
12.
Deficiency of vitamin K can occur in the following
conditions, except :
(a) Following gastrectomy
(b) Prolonged antibiotic therapy
(c)Obstructive jaundice
(d) Administration of dicoumarol
13.
In the structure of vitamin B, there is a :
(a) Aldehyde group
(b) Thiazole ring
(c) Pyridine ring
(d) Carboxyl group
14.
The following enzyme reaction is biotin dependent :
(a) Pyruvate Carboxylase (pyruvate to oxaloacetate)
(b) Pyruvate dehydrogenase (Pyruvate to acetyl COA)
(c) Pyruvate glycinate (Phosphoenol pyruvate to Pyruvate)
(d) None of the above
15.
All the compounds listed below act as antivitamins
except :
(a) Avidin
(c) INH
(b) Menadione
(d) Methotrexate
(e) Pyrimethamine
16.
The intrinsic white injury factor is
(a) Avidin
(b) Biotin
(c) Isoniazid
(d) Lipoic acid
17.
Pernicious anemia is caused by:
(a) Inadequate intake of vitamin B
(b) Deficiency of ascorbic acid ;
(c)Absence of intrinisic factor of the gastric justice
(d)Over production of extrinsic factor
18.
Which one of the following comounds is excreted in urine, in vitamins B, deficiency:
(a) Homocysteine
(b) Xanthurenic acid
(c) Parahydroxy phenyl pyruvic acid
(d) Methyl malinic acid
19.
Vitamin B, is required for the :
(a) Conversion of glycine to serine
(b) Production of gamma aminobutyric acid(GABA)
(cProduction of xanthurenic acid
(d) Decarboxylation of pyruvate
20. Deficiency of vitamin B, is manifested as :
(a) Scurvy
(b) Rickets
(c) Infantile convulsion
(d) Pellagra
(d) All of the above
21.
Biochemical function of vitamin K is for the :
(a) Formation of collagen by converting proline
to hydroxyproline
(b) Conversion of prothromin to thrombin
(c)Gamma carboxylation of clothing factors
(d) Inhibitionof lipid peroxidation in biomembrane
22.
All water soluble vitamins are excreted through urine and are not stored in the body except :
(a) vit. B,
(b) vit. B,
(c)vit. C
(d) Niacin
23.
Pellagra is due to the deficiency of:
(a) Niacin
(b) Thiamine
(c) vit.Bi2
(d) vit. C
24. Methyl. malonic acid is excreted in urnine in the
deficiency of :
(a) Folic acid
(b) Niacin
(c) Pyriodoxal phosphate
(d) vit. Biz
25.
The structure of vitamin E contains :
(a) Beta ionone ring
(b) Pteridine ring
(c) Chromane ring
(d) Thiazole ring
26.
The structure of vitamin K contains :
(a) Chromane ring
(b) Thiazole ring
(c) Naphthoquinone ring
(d) Iso alloxizine ring
27. Deficiency of folic acid leads to :
(a) Night blindness
(b) Rickets
(c)Macrocytic anaemia
(d) Microcytic anaemia
28.
The structure of biotin contains :
(a)Pyridine ring
(b) Imidazole ring
(c)Corrin ring
(d) Pteridine ring
29.
The structure of thiamine contains :
(a) Chromane ring
(b) Beta ionnone ring
(c) Thiazole ring
(d) Iso alloxazine ring
30.
The structure of riboflavin contains :
(a) Chromane ring
(b) Betaionone ring
(c)Thiazole ring
(d) Iso alloxazine ring
31.
The structure of niacin contains :
(a) Pyridine ring
(b) Corrin ring
(c) Imidazole ring
(d) Pteridine ring
32.
All compounds listed below act as competitive
inhibitors of enzymes, except :
(a) methotrexate
(b) Fluoride
(c) Allopurinol
(d) Sulfonamide
33.
The enzyme belonging to the class ligase is :
(a) Glycogen syntheses
(b) Porphobilinnogen deaminase
(c) Glutamine syntheses
(d) Histidine decarboxylase
34.
One of the following enzymes require chloride ions
as activators :
(a) Lipase
(b) Amylase
(c) Trypsin
(d) Chymotrypsinn
35.
All the following statements are true with regard
to non-competitive inhibition, except :
(a) Heavy metals are non-competitive type of
enzyme inhibitors
(b) Heavy metals inactivates sulfhydryl group of
enzymes
(c) BAL is an antidote for heavy metal poisoning
(d) BAL has several sulfhydryl groups with
which heavy metals can react and thereby
their poisonous effect is reduced
(e) BAL can reverse the inhibition of enzyme by
heavy metals
36.
All the following statements are true with regard to the optimum pH of enzymes, except
(a) At the optimum pH, the catalytic groups at the active centre of the enzyme have no net change
(b) At higher and lower pH, the tertiary structure
(c)of the protein may not be correct Optimum pH of pepsin is between 1 and 2
(d) Optimum pH of trypsin is about 8
37.
Glucokinase is more active after a meal, because :
(a) Glucokinase is present in all tissues
(b) Glucokinase can act on all monosaccharides increase
(c) Increase in serum ALT level is diagnostic
(d) Total LDH activity is not altered
18. Serum acid phosphates (ACP) level is increased in
(a) Rickets
(b) Hepatoma
(c) Prostatic carcinoma
(d) Acidosis
39.
Acetazolamide is the inhibitor of enzyme :
(a) Xanthine oxidase (b) Carbonic anhydrase
(c) Cycloxygenase
(d) Ligases
40.
Simvastatin is the inhibitor of enzyme
(a) HMG-COA reductase
(b)Glutamate Carboxylate
(c) Cycloxygenase
(d) Xanthine oxidase
41.
Enzymes that uncouple peptide linkages are best
classified as::
(a) Hydrolases
(b) Ligases
(c) Oxido reductases
(d) Transferases
(e) Isomerases
42.
Which of the following terms best describes a cofactor that is firmly bound to an apoenzyme:
(a) Heloenzyme
(b) Prosthetic group
(c) Coenzyme
(d) Transferabe
(e) Heteropolysaccharide
43.
The following are salient features of allosteric enzymes, except
(a) They are usually multiple subunit enzymes
(b) They are involved in metabolic regulation
(c) They give a sigmoid graph when substrate concentration [s] is ploolted against velocity
[v]
(d) They do not show any change in K_ and V in the presence of modifiers
44.
All the following statements are true with regard
to enzymes, except :
(a) Enzymes lower activation energy
(b) They alter equilibrium of the reaction
(c) They accelerate the chemical reaction
(d) Most of the enzymes are proteins in nature
(e) Enzymes are inactivated by protein
precipitating reagents
45.
All the following statements are true with regard
to coenzymes except :
(a) They function as co-substrate
(b) They are generally heat stable
eni
(c) They do not undergo chemical change during
the reaction
(d) They are small molecular weight substances
and are dialyzable
(e) Most of them are derived from vitamins
46.
Peptidases are categorized under which class of
enzymes :
(a) Oxido reductase
(b) Transferases
(c) Hydrolases
(d) Ligases
(e) Isomerases
47.
In non-competitive inhibition :
(a) The concentration of active enzyme molecules remains constant
(b) Vmax is increased and k is decreased
(c) Inhibition of succinate dehydrogenase by
malonate is an example
(d) Km is unaltered and V is reduced max
48.
When an enzyme functions with a co-enzyme, the co-enzyme:
(a) Increase the affinity of apo-enzyme to substrate
(b) Lowers the activation energy
(c) Increases the number of active sites on the enzsyme
(d) Accepts one of the products of the reaction
49.
Active centre of an enzyme :
(a) Has a rigid shape
(b) Is preserved even after denaturation
(c) Binds the substrate by non covalent bonds
(d) Is kept by the primary structure alone
50.
Enzymes may be used for the following, except :
(a) As therapeutic agents
(b) For diagnostic purposes
(c) As nutrients
(d)AS timor markers
(e)for commercial clearing agent
ANSWER
