Description : Vitamin K is involved in posttranslational modification of the blood clotting factors by acting as cofactor for the enzyme: (A) Carboxylase (B) Decarboxylase (C) Hydroxylase (D) Oxidase
Last Answer : Answer : A
Description : Vitamin K is involved in posttranslational modification of the blood clotting factors by acting as cofactor for the enzyme (A) Carboxylase (B) Decarboxylase (C) Hydroxylase (D) Oxidase
Last Answer : (A) Carboxylase
Description : Assertion: Platelets play an important role in blood clotting. Reason: In the blood oozing from an injury, the platelets disintegrate and release thro
Last Answer : Assertion: Platelets play an important role in blood clotting. Reason: In the blood oozing from an ... D. If both Assertion & Reason are false.
Description : Enzymic deficiency in β-aminoisobutyric aciduria is (A) Adenosine deaminase (B) Xanthine oxidase (C) Orotidylate decarboxylase (D) Transaminase
Last Answer : Answer : D
Description : The following enzymes on the left are responsible for the synthesis of the neurotransmitters on the right: a. monoamine oxidase: noradrenaline b. cholinesterase: acetylcholine c. catechol-o-methyl transferase: dopamine d. dopa decarboxylase: adrenaline
Last Answer : dopa decarboxylase: adrenaline
Description : How do platelets initiate blood clotting? -Biology
Last Answer : answer:
Description : Which of these components of the blood is responsible for clotting - (1) R.B.C. (2) Lymphocytes (3) Monocytes (4) Platelets
Last Answer : (4) Platelets Explanation: Coagulation is the process by which blood forms clots. It is an important part of hemostasis, the cessation of blood loss from a damaged vessel, wherein a ... begins almost instantly after an injury to the blood vessel has damaged the endothelium lining the vessel.
Description : The following are true about blood coagulation: a. heparin inhibits blood coagulation through its interference with vitamin K metabolism in the liver b. addition of vitamin K to freshly drawn ... delays clotting c. thrombin converts fibrinogen to fibrin d. platelets are essential for blood clot
Last Answer : thrombin converts fibrinogen to fibrin
Description : A patient who has been taking quantities of aspirin might show increased post operative bleeding because aspirin inhibits:** A. Synthesis of thromboxane A2 and prevents platelet aggregation B. ... network E. Increase the absorption of vitamin K and prevents synthesis of blood clotting factors
Last Answer : A. Synthesis of thromboxane A2 and prevents platelet aggregation
Description : When a wound occurs in humans, the platelets in th blood activate a substance which starts the clotting process. The substance which starts the clotting is: a) adenosine (pron: ah-den-ah-seen) b) histamine c) lecithin (pron: less-ah-thin) d) thrombin
Last Answer : ANSWER: D -- Thrombin
Description : Which of these components of the blood is responsible for clotting ? (1) R.B.C. (2) Lymphocytes (3) Monocytes (4) Platelets
Last Answer : Platelets
Description : Which enzyme is concerned with transfer of electrons? (A) Desmolase (B) Hydrolase (C) Dehydrogenase (D) Transaminase
Description : Tyrosinosis is due to defect in the enzyme: (A) Fumarylacetoacetate hydrolase (B) p-Hydroxyphenylpyruvate hydroxylase (C) Tyrosine transaminase (D) Tyrosine hydroxylase
Description : Orotic aciduria type II reflects the deficiency of the enzyme: (A) Orotate phosphoribosyl transferase (B) Orotidylate decarboxylase (C) Dihydroorotase (D) Dihydroorotate dehydrogenase
Last Answer : Answer : B
Description : An enzyme of pyrimidine nucleotide biosynthesis sensitive to allosteric regulation is (A) Aspartate transcarbamoylase (B) Dihydroorotase (C) Dihydroorotate dehydrogenase (D) Orotidylic acid decarboxylase
Description : Conversion of deoxyuridine monophosphate to thymidine monophosphate is catalysed by the enzyme: (A) Ribonucleotide reductase (B) Thymidylate synthetase (C) CTP synthetase (D) Orotidylic acid decarboxylase
Description : Histamine is formed from histidine by the enzyme histidine decarboxylase in the presence of (A) NAD (B) FMN (C) HS-CoA (D) B6-PO4
Description : An enzyme involved in catabolism of catecholamines is (A) Dopa decarboxylase (B) Aromatic amino acid decarboxylase (C) Monoamine oxidase (D) Catechol oxidas
Last Answer : Answer : C
Description : The enzyme catalyzing conversion of androstenedione to testosterone is a (A) Oxygenase (B) Dehydrogenase (C) Isomerase (D) Decarboxylase
Description : In the synthetic pathway of epinephrine, disulfiram (antabuse) inhibits the enzyme: (A) Tyrosine hydroxylase (B) Dopamine β-hydroxylase (C) DOPA decarboxylase (D) N-methyl transferase
Description : For Catecholamine biosynthesis the rate limiting enzyme is (A) DOPA decarboxylase (B) DOPAMINE β-hydroxylase (C) Tyrosine hydroxylase (D) Phenylalanine hydroxylase
Description : The enzyme involved in variegate porphyria is (A) Protoporphyrinogen oxidase (B) Coproporphyrinogen oxidase (C) Uroporphyrinogen decarboxylase (D) ALA decarboxylase
Description : Conversion of uroporphyrinogen III to coprophyrinogen III is catalysed by the enzyme.: (A) Uroporphyrinogen decarboxylase (B) Coproporphyrinogen oxidase (C) Protoporphyrinogen oxidase (D) Ferrochelatase
Description : Biotin is a coenzyme of the enzyme (A) Carboxylase (B) Hydroxylase (C) Decarboxylase (D) Deaminase
Description : An inborn error, maple syrup urine disease is due to deficiency of the enzyme: (A) Isovaleryl-CoAhydrogenase (B) Phenylalnine hydroxylase (C) Adenosyl transferase (D) α-Ketoacid decarboxylase
Description : The α-ketoacid is decarboxylated by H2O2 forming a carboxylic acid with one carbon atom less in the absence of the enzyme: (A) Catalase (B) Decarboxylase (C) Deaminase (D) Phosphatase
Description : The defective enzyme in histidinemia is (A) Histidine carboxylase (B) Histidine decarboxylase (C) Histidase (D) Histidine oxidase
Description : Which of the following enzyme defects is associated with a characteristic body odour? 1) Phenylalanine aminotransferase 2) Galactose0-phosphate-uridyltransferase 3) Ornithine transcarbamylase deficiency 4) Fumaryl acetoacetase 5) Branched chain ketoacid decarboxylase
Last Answer : Answers-5 The following inborn errors of amino acid metabolism are associated with abnormal odours: Glutaric acidaemia type II (sweaty feet), hawkinsinuria (swimming pool), isovaleric acidaemia (sweaty feet), ... The general rule is that if a child smells peculiar he requires a metabolic work-up.
Description : Aspirin prolongs bleeding time by inhibiting the synthesis of: A. Clotting factors in liver B. Prostacyclin in vascular endothelium C. Cyclic AMP in platelets D. Thromboxane A2 in platelets
Last Answer : D. Thromboxane A2 in platelets
Description : Enzyme first used for nitrogen fixation (a) nitrogenase (b) nitroreductase (c) transferase (d) transaminase.
Last Answer : (a) nitrogenase
Description : Given below are four statements (i-iv) regarding human blood circulatory system. (i) Arteries are thick-walled and have narrow lumen as compared to veins. (ii) Angina is acute chest pain when the blood circulation to the brain is ... (iv) (b) (i) and (ii) (c) (ii) and (iii) (d) (iii) and (iv)
Last Answer : (a) (i) and (iv)
Description : Following enzyme is involved in the synthesis of actylcholine (a) Choline acetyl transferase (b) Acetyl cholinesterase (c) Both (a) and (b) (d) None of the above
Last Answer : Ans: A
Description : Pralidoxime can reactivate cholinesterase enzyme that has been inactivated by: A. Carbamate anticholinesterases B. Organophosphate anticholinesterases C. Both carbamate and organophosphate anticholinesterases D. Reversible anticholinesterases
Last Answer : B. Organophosphate anticholinesterases
Description : The organophosphates produce irreversible inhibition of cholinesterase because: A. They bind to an allosteric site of the enzyme resulting in unfavourable conformation of esteratic site to bind ... degradation of enzyme molecules D. They are neither metabolized nor excreted from the body
Last Answer : B. Regeneration time of the phosphorylated enzyme is longer than the turnover time of the enzyme molecules
Description : Reactivation of cholinesterase enzyme occurs on hydrolysis of the inhibitor by the same enzyme molecule in case of the following anticholinesterase: A. Edrophonium B. Neostigmine C. Dyflos D. Tacrine
Last Answer : B. Neostigmine
Description : The following inhibitor binds only to the ani-onic site of the cholinesterase enzyme: A. Neostigmine B. Physostigmine C. Edrophonium D. Dyflos
Last Answer : C. Edrophonium
Description : Oils are partially hydrogenated (not fully) to manufacture Vanaspati, because fully saturated solidified oils (A) Cause cholesterol build up and blood clotting (B) Are prone to rancid oxidation (C ... (as their complete removal is very difficult) (D) Have affinity to retain harmful sulphur compounds
Last Answer : (A) Cause cholesterol build up and blood clotting
Description : The rate limiting enzyme in the synthesis of catecholamines is: A. Tyrosine hydroxylase B. Dopa decarboxylase C. Dopamine β-hydroxylase D. Noradrenaline N-methyl transferase
Last Answer : A. Tyrosine hydroxylase
Description : Platelets play an important role in haemostasis; which of the following describes this role? A. They convert fibrinogen to fibrin B. They agglutinate and plug small, ruptured ... thrombosis D. They supply fibrin stabilizing factors E. They supply proconvertin for thromboplastin activation
Last Answer : B. They agglutinate and plug small, ruptured vessels
Description : Which of the following cells or blood elements play a role in the initial phases of wound healing? a. Polymorphonuclear leukocytes (PMNs) b. Platelets c. Monocytes d. Lymphocytes
Last Answer : Answer: a, b, c, d Shortly after the initial injury, the wound is full of debris which is cleared over the next several days by recruited and activated phagocytic cells. ... in the initial hemostatic process as well as releasing chemotactic factors and factors leading to fibroblast proliferation
Description : Tryptophan pyrolase is currently known as (A) Tryptophan deaminase (B) Tryptophan dioxygenase (C) Tryptophan mono oxygenase (D) Tryptophan decarboxylase
Description : Maple syrup urine disease results from absence or serve deficiency of (A) Homogentisate oxidase (B) Phenylalanine hydroxylase (C) Branched chain amino acid transaminase (D) None of these
Description : An autosomal recessive disorder, xanthinuria is due to deficiency of the enzymes: (A) Adenosine deaminase (B) Xanthine oxidase (C) HGPRTase (D) Transaminase
Description : Iron is a component of (A) Hemoglobin (B) Ceruloplasmin (C) Transferase (D) Transaminase