Description : 3-β-Hydroxysteroid dehydrogenase and ∆5,4 isomerase catalyse the conversion of the weak androgen DHEA to (A) Androstenedione (B) Testosterone (C) Progesterone (D) Estrone
Last Answer : Answer : A
Description : Precursor of ACTH is (A) Cholesterol (B) Pregnenolone (C) Corticotropin (D) Pro-opiomelanocortin
Last Answer : Answer : D
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 : All the following statements about angiotensin are true except (A) Its precursor is an α2-globulin (B) Its active form is an octapeptide (C) It is a vasodilator (D) It increases the secretion of aldosterone
Last Answer : Answer : C
Description : Spironolactone is an antagonist of (A) Cortisol (B) Hydrocortisone (C) Aldosterone (D) Testosterone
Description : A common intermediate in the synthesis of cortisol and aldosterone is (A) Progesterone (B) Testosterone (C) Estradiol (D) None of these
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
Description : Bradykinin and angiotensin II have the following feature common to both: A. They both cause fall in BP B. They both are degraded by Kininase II C. Their precursor proteins are plasma α2 globulins D. They both release aldosterone from adrenal cortex
Last Answer : C. Their precursor proteins are plasma α2 globulins
Description : Methyl dopa decreases blood pressure by (A) Inhibiting the synthesis of catecholamines (B) Antagonising the action of aldosterone (C) Stimulating the release of renin (D) Inhibiting the breakdown of angiotensin
Description : Lack of Glucocorticoids and mineral corticoids might be consequence of which of the following defects in the adrenal cortex? (A) Androstenadione deficiency (B) Estrone deficiency (C) 17 α-OH progesterone deficiency (D) C- α-Hydroxylase deficiency
Description : The major metabolite of progesterone is (A) Pregnenolone (B) Pregnanediol (C) Estradiol (D) Norethindrone
Last Answer : Answer : B
Description : A common intermediate in the synthesis of all the steroid hormones is (A) Pregnenolone (B) 17-Hydroxypregnenolone (C) Corticosterone (D) Progesterone
Description : Synthetic progesterone used in oral contraceptive is (A) Norethindrone (B) Pregnenolone (C) Androstenodione (D) Stilbestrol
Description : Main metabolic end product of cholesterol: (A) Coprosterol (B) 5-pregnenolone (C) Bile acid (D) Glycine
Description : The following androgen does not produce cholestatic jaundice as an adverse effect: A. Testosterone propionate B. Methyl testosterone C. Fluoxymesterone D. Stanozolo
Last Answer : A. Testosterone propionate
Description : The mechanism of synthesis of DNA and RNA are similar to all the following ways except (A) They involve release of pyrophosphate from each nucleotide added (B) They require activated nucleotide precursor and Mg2+ (C) The direction of synthesis is (D) They require a primer
Description : Insoinic acid is the biological precursor of (A) Cytosine and Uric acid (B) Adenylve acid and Glucine floc acid (C) Orotic acid and Uridylic acid (D) Adenosine acid Thymidine
Description : The mechanism of synthesis of DNA and RNA are similar in all the following ways except (A) They involve release of pyrophosphate from each nucleotide added (B) They require activated nucleotide precursor and Mg2+ (C) The direction of synthesis is 5’ → 3’ (D) They require a primer
Description : All of the following statements about tRNA are true except (A) It is synthesized as a large precursor (B) It is processed in the nucelolus (C) It has no codons or anticodons (D) Genes for rRNA are present in single copies
Description : Heterogeneous nuclear RNA is the precursor of (A) mRNA (B) rRNA (C) tRNA (D) None of these
Description : Pyrimidine and purine nucleoside biosynthesis share a common precursor: (A) PRPP (B) Glycine (C) Fumarate (D) Alanine
Description : All the following statements about βendorphin are true except µ : (A) It is a polypeptide (B) Its precursor is pro-opio-melanocortin (C) Its receptors are represent in brain (D) Its action is blocked by morphine
Description : Immediate precursor of epinephrine is (A) Metanephrine (B) Norepinephrine (C) Dopa (D) Dopamine
Description : All the following statements about proopiomelanocortin are true except (A) It is made up of 285 amino acids (B) It is synthesised in pars intermedia and anterior lobe of pituitary gland ... ) It is the precursor of corticotropin like intermediate lobe peptide and endorphins 218 MCQs IN BIOCHEMISTRY
Description : Zymogen is a (A) Vitamin (B) Enzyme precursor (C) Modulator (D) Hormone
Description : The common precursor in the biosynthesis of triacylglycerol and phospholipids is (A) 1, 2-Diacylglycerol phosphate (B) 1-Acylglycerol 3-phosphate (C) Glycerol 3-phosphate (D) Dihydroxyacetone phosphate
Description : Which of the following intermediates of metabolism can be both a precursor and a product of glucose? (A) Lactate (B) Pyruvate (C) Alanine (D) Acetyl-CoA
Description : Cholesterol is a precursor in the biogenesis of (A) Vitamin A (B) Vitamin D (C) Vitamin E (D) None of these
Description : Precursor of Vitamin A is (A) α-Carotene (B) β-Carotene (C) γ-Carotene (D) All of these VITAMINS 121
Description : The precursor of CoA is (A) Riboflavin (B) Pyridoxamine (C) Thiamin (D) Pantothenate
Description : β-Carotene, precursor of vitamin A, is oxidatively cleaved by (A) β-Carotene dioxygenase (B) Oxygenase (C) Hydroxylase (D) Transferase
Description : Cholesterol is the precursor for the biosynthesis of (A) fatty acid (B) prostaglandins (C) bile acids (D) sphingmyelin
Description : The precursor of bile salts, sex hormones and vitamin D is (A) Diosgenin (B) Cholesterol (C) Campesterol (D) Ergosterol
Description : All the following statements about pepsin are correct except (A) It is smaller than pepsinogen (B) It is formed by the action of HCl on its precursor (C) Its optimum pH is 1.0–2.0 (D) It hydrolyses the C-terminal and N-terminal peptide bonds of proteins
Description : Tryptophan could be considered as precursor of (A) Melanotonin (B) Thyroid hormones (C) Melanin (D) Epinephrine
Description : In mammalian tissues serine can be a biosynthetic precursor of (A) Methionine (B) Glycine (C) Tryptophan (D) Phenylalanine
Description : Phenylalanine is the precursor of (A) L-DOPA (B) Histamine (C) Tyrosine (D) Throxine
Last Answer : C
Description : What is the precursor of leukotrienes?
Last Answer : They are produced from arachidonic acid.
Description : Muscle glycogen will not serve as a precursor of blood sugar, why?
Last Answer : Glucose-6-phosphatase is absent in muscle.
Description : A diuretic which is an aldosterone antagonist is (A) Spironolactone (B) Ethacrynic acid (C) Acetazolamide (D) Chlorothiazide
Description : Thiazide diuretics inhibit (A) Carbonic anhydrase (B) Aldosterone secretion (C) ADH secretion (D) Sodium reabsorption in distal tubules
Description : Diabetes insipidus results from (A) Decreased insulin secretion (B) Decreased ADH secretion (C) Decreased aldosterone secretion (D) Unresponsiveness of osmoreceptors
Description : Potassium metabolism is regulated by the hormone: (A) Aldosterone (B) PTH (C) Somatostatin (D) Estrogen
Description : The metabolism of sodium is regulated by the hormone: (A) Insulin (B) Aldosterone (C) PTH (D) Somatostatin
Description : Increased reabsorption of water from the kidney is the major consequence of which of the following hormones? (A) Cortisol (B) Insulin (C) Vasopressin (D) Aldosterone
Description : Which of the following hormone is not under the control of ACTH? (A) Aldosterone (B) Cortisol (C) Corticosterone (D) Deoxycorticosterone
Description : The most potent hormone concerned with the retention of sodium in the body is (A) Cortisone (B) Aldosterone (C) Corticosterone (D) Cortisol
Description : All the following statements about transcortin are true except (A) It is synthesised in liver (B) It transports glucocorticoids (C) It transports aldosterone (D) It transports progesterone
Description : The major mineralcorticoid is (A) Hydrocortisone (B) Aldosterone (C) Aldactone A (D) Androstenedione