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
Last Answer : Answer : D
Description : A provitamin D synthesized in human beings is (A) Ergosterol (B) 7-Dehydrocholesterol (C) Cholecalciferol (D) 25-Hydroxycholecalciferol
Last Answer : Answer : B
Description : The structure shown below is of (A) Cholecalciferol (B) 25-Hydroxycholecalciferol (C) Ergocalciferol (D) 7-Dehydrocholesterol
Last Answer : Answer : A
Description : Tubular reabsorption of calcium is increased by (A) Cholecalciferol (B) 25-Hydroxycholecalciferol (C) Calcitriol (D) All of these
Last Answer : Answer : C
Description : Steroid hormones are synthesised from (A) Cholesterol (B) 7-Dehydrocholesterol (C) Calcitriol (D) 7-Hydroxycholesterol
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 : The most potent Vitamin D metabolite is (A) 25-Hydroxycholecalciferol (B) 1,25-Dihydroxycholecalciferol (C) 24, 25-Dihydroxycholecalciferol (D) 7-Dehydrocholesterol
Description : Women become susceptible to osteoporosis after menopause due to decreased (A) Secretion of Parathormone (B) Conversion of vitamin D into calcitriol (C) Secretion of estrogen (D) Secretion of progesterone
Last Answer : (B) 1,25-Dihydroxycholecalciferol
Description : Calcitriol is (A) 1-hydroxy cholecalciferol (B) 25-hydroxy cholecalciferol (C) 24, 25-dihydroxy cholecalciferol (D) 1, 25-dihydroxy cholecalciferol
Description : Calcitriol is (A) 1-OH-cholecalciferol (B) 25-OH-cholecalciferol (C) 24, 25-diOH cholecalciferol (D) 1, 25-diOH cholecalciferol
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 : 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 : The most suitable vitamin D preparation for vitamin D dependent rickets is: A. Calciferol B. Cholecalciferol C. Calcifediol D. Calcitriol
Last Answer : D. Calcitriol
Description : This interferes with cholesterol absorption (A) Lipoprotein lipase (B) Creatinase (C) 7-dehydrocholesterol (D) β-sitosterol
Description : The most active form of Vitamin D is (A) 25-Hydroxycholecalciferol (B) 1, 25-dihydroxycholecalciferol (C) 25-dihydroxyergocalciferol (D) None of these
Description : The normal serum concentration of 25-hydroxycholecalciferol in ng/ml is (A) 0–8 (B) 60–100 (C) 100–150 (D) 8–55
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 : Hydroxylation of 25-hydroxy cholecalciferol is promoted by (A) Cytochrome A (B) Panthyroid hormone (C) Cytochrome b (D) cAMP
Description : Hydroxylation of 25-hydroxy cholecalciferol is promoted by (A) Cytochrome - a (B) Parathyroid hormone (C) Cytochrome-b (D) CAMP
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 : cis-acting elements include (A) Steroid hormones (B) Calcitriol (C) Histones (D) Silencers
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 : Calcitriol facilitates calcium absorption by increasing the synthesis of the following in intestinal mucosa: (A) Calcium Binding Protein (B) Alkaline Phosphatase (C) Calcium-dependent ATPase (D) All of these
Description : Calcitriol synthesis involves (A) Both liver and kidney (B) Intestine (C) Adipose tissue (D) Muscle
Description : The sequence of amino acid in which the biological value of parathormone is (A) 1–15 (B) 1–34 (C) 30–50 (D) 50–84
Description : The number of amino acids in parathormone is (A) 65 (B) 84 (C) 115 (D) 122
Description : Plasma calcium is lowered by (A) Parathormone (B) Calcitonin (C) Aldosterone (D) Deoxycorticosterone
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 : Activated lecithin cholesterol acyl transferase is essential for the conversion of (A) VLDL remnants into LDL (B) Nascent HDL into HDL (C) HDL2 into HDL3 (D) HDL3 into HDL2
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 : Characteristics of Vitamin D and its metabolites include which one of the following? (a) Act to decrease serum levels of calcium (b) Activation of their Vitamin D receptors increases cellular CAMP ... Vitamin D increase renal excretion of calcium (e) Vitamin D deficiency results in Pager's disease
Last Answer : Ans: C
Description : 6.2 Which hormone acts through a cytoplasmic receptor: A. Calcitriol B. Prolactin C. Vasopressin D. None of the abov
Last Answer : A.Calcitol binds to cytoplasmic membrane and enhances the absorption of Calcium by increasing the calcium binding proteins-calbindin-D proteins.
Description : Parathormone is secreted during
Last Answer : Parathormone is secreted during A. Increased blood calcium level B. Decreased blood calcium level C ... sugar level D. Decrease blood sugar level
Description : Parathormone influences calcium absorbton in the small intestine by regulating the metabolim of
Last Answer : Parathormone influences calcium absorbton in the small intestine by regulating the metabolim of A. Vitamin C ... D C. Vitamin `B_6` D. Enterogastrone
Description : Parathormone induces
Last Answer : Parathormone induces A. Increase in blood sugar level B. Decrease in serum calcium level C. ... calcium level D. Decrease in blood sugar level
Description : Parathormone deficiency causes
Last Answer : Parathormone deficiency causes A. Goiter B. Hypocalcemia C. Hypercalcemia D. All of the above
Description : Which gland produces the enzyme parathormone?
Last Answer : Parathyroid
Description : The blood calcium level is lowered by the deficiency of (a) both calcitonin and parathormone (b) calcitonin (c) parathormone (d) thyroxine
Last Answer : (c) parathormone
Description : Which of the following pairs of hormones are not antagonistic (having opposite effects) to each other? (a) Aldosterone Atrial Natriuretic Factor (b) Relaxin Inhibin (c) Parathormone Calcitonin (d) Insulin Glucagon
Last Answer : (b) Relaxin Inhibin
Description : Duodenum has characteristic Brunner’s gland which secrete two hormones called (a) kinase, estrogen (b) secretin, cholecystokinin (c) prolactin, parathormone (d) estradiol, progesterone
Last Answer : (b) secretin, cholecystokinin
Description : The drug of choice for hypoparathyroidism is: A. Parathormone B. Calcium lactate C. Vitamin D D. Pamidronate
Last Answer : C. Vitamin D
Description : Bone resorption is accelerated by: A. Estrogens B. Parathormone C. Bisphosphonates D. Calcitonin
Last Answer : B. Parathormone
Description : Corporate executives who work in top notch companies and travel to their offices in early morning in their air conditioned cars with tinted glasses spending their entire day in their cabins are prone ... from the deficiency of: (a) calcitonin (b) cynacobalamin (c) tocopherol (d) cholecalciferol.
Last Answer : Ans:(b)
Description : A cofactor required for the conversion of acetyl-CoA to malonyl-CoA in extramitochondrial fatty acid synthesis is (A) Biotin (B) FMN (C) NAD (D) NADP
Description : Both folic acid and methyl cobalamin (vitamin B12) are required in (A) Deamination of serine (B) Deamination of threonine (C) Conversion of pyridoxal phosphate to pyridoxamine phosphate (D) Methylation of homocystein to methionine
Description : Vitamin required for metabolism of diols e.g. conversion of ethylene glycol to acetaldehyde is (A) Thiamin (B) Cobalamin (C) Pyridoxine (D) Folic acid