Description : Hydroxylation of 25-hydroxy cholecalciferol is promoted by (A) Cytochrome - a (B) Parathyroid hormone (C) Cytochrome-b (D) CAMP
Last Answer : Answer : B
Description : Calcitriol is (A) 1-hydroxy cholecalciferol (B) 25-hydroxy cholecalciferol (C) 24, 25-dihydroxy cholecalciferol (D) 1, 25-dihydroxy cholecalciferol
Last Answer : Answer : D
Description : 1-hydroxylation of 25-hydroxy Vitamin D3 takes place in (A) Liver (B) Kidneys (C) Intestine (D) Pancreas
Description : The active transport of ‘Ca’ is regulated by __________ which is synthesized in kidnyes. (A) Cholecalciferol (B) Ergosterol (C) 25-OH cholecalciferol (D) 1, 25-di OH-Cholecalciferol
Description : Calcitriol is (A) 1-OH-cholecalciferol (B) 25-OH-cholecalciferol (C) 24, 25-diOH cholecalciferol (D) 1, 25-diOH cholecalciferol
Description : Calcitriol inhibits the conversion of (A) Cholesterol into 7-dehydrocholesterol (B) Cholecalciferol into 1-hydroxycholecalciferol (C) Cholecalciferol into 25-hydroxycholecalciferol (D) 25-Hydroxycholecalciferol into 1,25- dihydroxycholecalciferol
Description : Parathormone is required for the conversion of (A) Cholecalciferol into 1-hydroxycholecalciferol (B) Cholecalciferol into 25-hydroxycholecalciferol (C) 25-Hydroxycholecalciferol into calcitriol (D) Cholesterol into 7-dehydrocholesterol
Last Answer : Answer : C
Description : Tubular reabsorption of calcium is increased by (A) Cholecalciferol (B) 25-Hydroxycholecalciferol (C) Calcitriol (D) All of these
Description : A provitamin D synthesized in human beings is (A) Ergosterol (B) 7-Dehydrocholesterol (C) Cholecalciferol (D) 25-Hydroxycholecalciferol
Description : The structure shown below is of (A) Cholecalciferol (B) 25-Hydroxycholecalciferol (C) Ergocalciferol (D) 7-Dehydrocholesterol
Last Answer : Answer : A
Description : In renal rickets, the following hydroxylation of Vitamin D3 does not take place: (A) 25 (B) 1 (C) 24 (D) 7
Description : 25-hydroxylation of Vitamin D3 takes place in (A) Liver (B) Kidneys (C) Intestines (D) Pancreas
Description : In retinal rickets, the following hydroxylation of Vitamin D3 does not take place: (A) 25 (B) 1 (C) 24 (D) 7
Description : 25-hydroxylation of vitamin D3 takes place in (A) Liver (B) Kidneys (C) Intestine (D) Pancreas
Description : 1-hydroxylation of 25-OH vitamin D3 takes place in (A) Liver (B) Kidneys (C) Intestine (D) Pancreas
Description : 25-Hydroxylation of vitamin D occurs in (A) Skin (B) Liver (C) Kidneys (D) Intestinal mucosa
Description : Secretion of somatotrophin is promoted by (A) Somatomedin C (B) Somatostatin (C) Growth hormone releasing hormone (D) Hypoglycaemia
Description : Secretion of Insulin-like Growth Factor-I is promoted by (A) Insulin (B) Glucagon (C) Growth hormone (D) Somatomedin C
Description : Hormone receptors that stimulate cAMP production (A) are part of a complex of two proteins that transform the external signal into internal cAMP production (B) are proteins distinct and separate from those ... binding of the hormone (D) are not very specific and bind a number of different hormones
Description : Hormone that bind to cell surface receptor and require the second messenger camp is (A) Antidiuretic hormone (B) Cholecystokinin (C) Calcitriol (D) Gastrin
Description : Covalent modification of an enzyme generally requires a (A) Hormone (B) cAMP (C) Protein kinase (D) All of these
Description : Which of the following regulates lipolysis in adipocytes? (A) Activation of fatty acid synthesis mediated by CAMP (B) Glycerol phosphorylation to prevent futile esterification of fatty acids (C) ... result of hormone stimulated increases in CAMP levels (D) Activation of CAMP production by Insulin
Description : Adipose tissue lacks (A) Hormone-sensitive lipase (B) Glycerol kinase (C) cAMP-dependent protein kinase (D) Glycerol-3-phosphate dehydrogenase
Description : A high plasma calcium level decreases intestinal absorption of calcium by (A) Stimulating the secretion of parathormone (B) Inhibiting the secretion of parathormone (C) Decreasing the synthesis of cholecalciferol (D) Inhibiting the secretion of thyrocalcitonin
Description : This is photo labile vitamin: (A) Thiamine (B) Riboflavin (C) Niacin (D) Cholecalciferol
Description : This is a photo-labile vitamin. (A) Thiamine (B) Riboflavin (C) Niacin (D) Cholecalciferol
Description : Dictary deficiency of this vitamin leads to night blindness: (A) Retinol (B) Niacin (C) Ascorbic acid (D) Cholecalciferol VITAMINS 125
Description : Provitamin D3 is (A) Cholecalciferol (B) Ergosterol (C) 7-Dehydrocholesterol (D) Ergocaliferol
Description : The β-ring of 7-dehydrocholesterol is cleaved to form cholecalciferol by (A) Infrared light (B) Dim light (C) Ultraviolet irridation with sunlight (D) Light of the tube lights
Description : One international unit (I.U) of vitamin D is defined as the biological activity of (A) 0.025 µg of cholecalciferol (B) 0.025 µg of 7-dehydrocholecalciferol (C) 0.025 µg of ergosterol (D) 0.025 µg of ergocalciferol VITAMINS 113
Description : A metabolite which is common to pathways of cholesterol biosynthesis from acetyl-CoA and cholecalciferol formation from cholesterol is (A) Zymosterol (B) Lumisterol (C) Ergosterol (D) 7 Dehydrocholesterol
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 : Epinephrine is derived from norepinephrine by (A) Decarboxylation (B) Hydroxylation (C) Oxidation (D) N-methylation
Description : The sequential steps in the conversion of tyrosine to epinephrine are (A) Ring hydroxylation-decarboxylation-side chain hydroxylation-N-methylation (B) Side chain hydroxylation-decarboxylation- ... chain hydroxylation-N-methylation (D) N-methylation-decarboxylation-ring and side chain hydroxylation
Description : Biotin is essential for (A) Translation (B) Carboxylation (C) Hydroxylation (D) Transamination
Description : Biotin is involved in which of the following types of reactions? (A) Hydroxylation (B) Carboxylation (C) Decarboxylation (D) Deamination
Description : Vitamin B1 coenzyme (TPP) is involved in (A) Oxidative decarboxylation (B) Hydroxylation (C) Transamination (D) Carboxylation
Description : Hydroxylation of Proline and Lysine in a protein is effected by (A) Vitamin B1 (B) Vitamin B2 (C) Vitamin B6 (D) Vitamin C
Description : Histidine is converted into histamine by (A) Carboxylation (B) Decarboxylation (C) Methylation (D) Hydroxylation
Description : The components of complement system are activated by (A) Microsomal hydroxylation (B) Phosphorylation (C) Glycosylation (D) Proteloysis
Description : Hydroxylation of phenylalanine requires all of the following except (A) Phenylalanine hydroxylase (B) Tetrahydrobiopterin (C) NADH (D) Molecular oxygen
Description : All of the following are required for hydroxylation of proline residues except (A) Ascorbic acid (B) Glutamate (C) Ferrous ions (D) Molecular oxygen
Description : All the following statement about hydroxyproline are true except (A) There is no codon for hydroxyproline (B) It is present in large amounts in collagen (C) Free proline cannot be hydroxylated to hydroxyproline (D) Hydroxylation of proline residues is catalysed by a dioxygenase
Description : The rate limiting step in the biosynthesis of catecholamines is (A) Decarboxylation of dihydroxyphenylalanine (B) Hydroxylation of phenylalanine (C) Hydroxylation of tyrosine (D) Oxidation of dopamine
Description : In the biosynthesis of testosterone the rate limiting step is conversion of (A) Cholesterol to pregnenolone (B) Pregnenolone to progesterone (C) Progesterone to 17 α-hydroxy progesterone (D) 17 α-Hydroxy progesterone to androstenedione
Description : Catecholamine hormones are (A) 3, 4-Dihydroxy derivatives of phenylethylamine (B) p-Hydroxy derivatives of phenylacetate (C) p-Hydroxy derivatives of phenylpyruvate (D) p-Hydroxy derivatives of phenyllactate
Description : Goitrogenic substance present in cabbage is (A) 5-vinyl-2 thio oxalzolidone (B) Pyridine-3-carboxylic acid (C) 3-Hydroxy-4, 5-dihydroxymethyl1–2-methyl pyridine (D) δ-ALA dehydratase
Description : Acetoacetyl-CoA condenses with one more molecule of acetyl-CoA to form (A) Mevalonate (B) Acetoacetate (C) β-Hydroxybutyrate (D) 3-Hydroxy 3-methyl-glutaryl-CoA
Description : The protein, which is in fact a multifunctional enzyme complex in higher organism is (A) Acetyl transacylase (B) Malonyl transacylase (C) 3-Hydroxy acyl-ACP dehyratase (D) Fatty acid synthase
Description : In the pathway leading to biosynthesis of acetoacetate from acetyl-CoA in liver, the immediate precursor of aceotacetate is (A) Acetoacetyl-CoA (B) 3-Hydroxybutyryl-CoA (C) 3-Hydroxy-3-methyl-glutaryl-CoA (D) 3-Hydroxybutyrate