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
Last Answer : Answer : B
Description : All of the following statements about thioredoxin reductase are true except: (A) It requires NADH as a coenzyme (B) Its substrates are ADP, GDP, CDP and UDP (C) It is activated by ATP (D) It is inhibited by dADP
Last Answer : Answer : A
Description : Conversion of tyrosine to dihydroxyphenylalanine is catalysed by tyrosine hydroxylase which requires (A) NAD (B) FAD (C) ATP (D) Tetrahydrobiopterin
Last Answer : Answer : D
Description : For reduction enzyme HMG-CoA reductase requires cofactor: (A) NADPH (B) NADP (C) NAD (D) FAD
Description : Galactose 1-phosphate is converted to uridine diphosphate galactose, the reaction is catalysed by the enzyme: (A) Glactokinase (B) Galactose 1-phosphate uridyl transferase (C) Uridine diphospho galactose 4-epimerase (D) UDP glucose pyrophosphorylase
Description : Uridine diphosphate glucose (UDPG) is (A) Required for metabolism of galactose (B) Required for synthesis of glucuronic acid (C) A substrate for glycogen synthetase (D) All of the above
Last Answer : D
Description : Hydroxylation of phenylalanine requires all of the following except (A) Phenylalanine hydroxylase (B) Tetrahydrobiopterin (C) NADH (D) Molecular oxygen
Last Answer : Answer : C
Description : Methotrexate blocks the synthesis of thymidine monophosphate by inhibiting the activity of the enzyme: (A) Dihydrofolate reductase (B) Orotate phosphoribosyl transferase (C) Ribonucleotide reductase (D) Dihydroorotase
Description : Reduction of ribonucleotide diphosphates (NDPs) to their corresponding deoxy ribonucleotide diphosphates (dNDPs) involves (A) FMN (B) FAD (C) NAD (D) NADPH
Description : Which of the following nucleoside diphosphates is used most often in carbohydrate anabolism? A.Uridine diphosphate B.Adenosine diphosphate C.Guanine diphosphate D.Thymine diphosphate
Last Answer : A.Uridine diphosphate
Description : Conversion of all-trans-retinal into alltrans-retinol requires (A) NAD (B) NADH (C) NADP (D) NADPH
Description : Conversion of retinal into ritonal requires the presence of (A) NADH (B) NADPH (C) FADH2 (D) Lipoic acid
Description : Conversion of folate into tetrahydrofolate requires (A) NADH (B) NADPH (C) FMNH2 (D) FADH2
Description : Reduction of D-ribonucleotides to Ddeoxy ribonucleotides in prokaryotes requires (A) 5, 6 dimethyl benzimidazole cobamide (B) Thioredoxin (C) Tetra hydrobiopterin (D) Tetra hydrofolate
Description : Retinal is reduced to retinol by retinene reductase in presence of the coenzyme (A) NAD+ (B) NADP+ (C) NADH + H+ (D) NADPH + H+
Description : Retinol and retinal are interconverted requiring dehydrogenase or reductase in the presence of (A) NAD or NADP (B) NADH + H+ (C) NADPH (D) FAD
Description : Retinal is reduced to retinol in intestinal mucosa by a specific retinaldehyde reductase utilising (A) NADPH + H+ (B) FAD (C) NAD (D) NADH + H+
Description : Fatty acids can not be converted into carbohydrates in the body, as the following reaction is not possible: (A) Conversion of glucose-6-phosphate into glucose (B) Fructose 1, 6 diphosphate to ... phosphate (C) Transformation of acetyl CoA to pyruvate (D) Formation of acetyl CoA from fatty acids
Description : Conversion of testosterone to dihydrotestosterone by the enzyme 5α-reductase is required for the following actions except: A. Formation of male external genitalia in the foetus B. Prostatic hypertrophy in elderly males C. Pubertal changes in the male adolescent D. Spermatogenesis
Last Answer : D. Spermatogenesis
Description : Conversion of fructose to sorbitol is catalysed by the enzyme: (A) Sorbitol dehydrogenase (B) Aldose reductase (C) Fructokinase (D) Hexokinase
Description : Thyroproxidase requires hydrogen peroxide as oxidizing agent. The H2O2 is produced by (A) FADH2 dependent enzyme (B) NADH dependent enzyme (C) NADP dependent enzyme (D) NADPH dependent enzyme
Description : Synthesis of sphingosine requires the cofactor (A) NAD (B) NADP (C) NADPH+ (D) ATP
Description : A pathway that requires NADPH as a cofactor is (A) Extramitochondrial folic acid synthesis (B) Ketone body formation (C) Glycogenesis (D) Gluconeogenesis
Description : A pathway that requires NADPH as a cofactor is (A) Fatty acid oxidation (B) Extra mitochondrial denovo fatty acid synthesis (C) Ketone bodies formation (D) Glycogenesis
Description : Mitochondrial lipogenesis requires (A) bicarbonate (B) biotin (C) acetyl CoA carboxylase (D) NADPH
Description : The first true pyrimidine ribonucleotide synthesized is (A) UMP (B) UDP (C) TMP (D) CTP
Description : For synthesis of sphingosine, all the following coenzymes are required except (A) Pyridoxal phosphate (B) NADPH (C) FAD (D) NAD
Description : Orotic aciduria can be controlled by (A) Oral administration of orotic acid (B) Decreasing the dietary intake of orotic acid (C) Decreasing the dietary intake of pyrimidines (D) Oral administration of uridine
Description : The T ψ C arm in the tRNA molecule possesses the sequence (A) T, pseudouridine and C (B) T, uridine and C (C) T, dihydrouridine and C (D) T, adenine and C
Description : In tRNA molecule D arm is named for the presence of the base: (A) Uridine (B) Pseudouridine (C) Dihydrouridine (D) Thymidine
Description : Uracil and ribose form (A) Uridine (B) Cytidine (C) Guanosine (D) Adenosine
Description : 5’-Terminus of mRNA molecule is capped with (A) Guanosine triphosphate (B) 7-Methylguanosine triphophate (C) Adenosine triphosphate (D) Adenosine diphosphate
Description : A substrate for the enzyme aldolase is (A) galactose-6-phosphate (B) isocitric acid (C) Glucose-1-phosphate (D) Fructose 1, 6 diphosphate
Description : Which of the following coenzyme takes part in oxidation-reduction reactions? (A) Pyridoxal phosphate (B) Lipoic acid (C) Thiamin diphosphate (D) None of these
Description : Thiamin diphosphate is required for oxidative decarboxylation of (A) α-Keto acids (B) α-Amino acids (C) Fatty acids (D) All of these
Description : During glycolysis, Fructose 1, 6 diphosphate is decomposed by the enzyme: (A) Enolase a (B) Fructokinase (C) Aldolase (D) Diphosphofructophosphatose
Last Answer : C
Description : Galactose is phosphorylated by galactokinase to form (A) Galactose-6-phosphate (B) Galactose-1, 6 diphosphate (C) Galactose-1-phosphate (D) All of these
Description : Conversion of a procarcinogen into a carcinogen often requires (A) Proteolysis (B) Microsomal hydroxylation (C) Exposure to ultraviolet radiation (D) Exposure to X-rays
Description : Conversion of β-carotene into retinal requires the presence of (A) β-Carotene dioxygenase (B) Bile salts (C) Molecular oxygen (D) All of these
Description : Conversion of testosterone to estradiol requires the enzyme: (A) Aromatase (B) Dehydrogenase (C) Lyase (D) Isomerase HORMONE METABOLISM 215
Description : The enzyme phosphoenolpyruvate carboxykinase catalyses the conversion of oxaloacetate to phosphoenolpyruvate requires (A) ATP (B) ADP (C) AMP (D) GTP
Description : The enzyme dopamine β-oxidase which catalyses conversion of dopamine to norepinephrine requires (A) Vitamin A (B) Vitamin C (C) Vitamin E (D) Vitamin B12
Description : Retinal is converted into retinoic acid in the presence of (A) Retinal oxidase (B) Retinal carboxylase (C) Retinene reductase(D) Spontaneously
Description : Which of the following statement(s) is/are true concerning DNA? a. DNA is contained only in the nucleus of the cell b. DNA strands are encoded by the sequence of four bases-adenine, guanine, cytosine ... DNA is the intron, a sequence of three bases d. There are an infinite number of possible codons
Last Answer : Answer: a The genetic blueprint of an organism is carried in the nucleus of every cell, encoded by the sequence of four bases-adenine, guanine, cytosine and thymine, which together make up ... codons. Sixty-one of these code for amino acids and three are termination signals called stop codons
Description : Uridine, present only in RNA is a (a) nucleoside (b) nucleotide (c) purine (d) pyrimidine.
Last Answer : a) nucleoside
Description : The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that adenosine triphosphate (ATP) is formed because (a) a proton gradient forms across the inner membrane (b) there is a ... mitochondrial proteins (d) ADP is pumped out of the matrix into the intermembrane space.
Last Answer : (a) a proton gradient forms across the inner membrane
Description : Cancer cells may become resistant to amethopterin by (A) Developing mechanisms to destroy amethopterin (B) Amplification of dihydrofolate reducatse gene (C) Mutation in the dihydrofolate reductase ... is no longer inhibited by amethopterin (D) Developing alternate pathway of thymidylate synthesis
Description : Amplification of dihydrofolate reductase gene in a cancer cell makes the cell (A) Susceptible to folic acid deficiency (B) Less malignant (C) Resistant to amethopterin therapy (D) Responsive to amethopterin therapy
Description : Amplification of dihydrofolate reductase gene may be brought about by (A) High concentrations of folic acid (B) Deficiency of folic acid (C) Low concentration of thymidylate (D) Amethopterin
Description : Ceruloplasmin shows the activity (A) As ferroxidase (B) As reductase (C) As ligase (D) As transferase