Description : Corticotropin releasing hormone controls the direct release of (A) Pro-opiomelanocortin (B) α MSH (C) β MSH (D) Endorphins
Last Answer : Answer : A
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
Last Answer : Answer : C
Description : Regulation of ACTH secretion occurs through (A) Corticotropin releasing hormone (CRH) and corticotropin release inhibiting hormone (CRIH) of hypothalamus (B) Feedback inhibition by cortisol (C) CRH and feedback inhibition by cortisol (D) CRIH and feedback inhibition by cortisol
Description : The precursor of testosterone is (A) Aldosterone (B) Methyl testosterone (C) Estrone (D) Pregnenolone
Last Answer : Answer : D
Description : The immediate parent of α, β and γ endorphins is (A) Pro-opiomelanocortin (B) β-lipotropin (C) ATCH (D) Lipoprotein
Last Answer : Answer : B
Description : All of the following can be formed from pro-opiomelanocortin except (A) α-and β-MSH (B) β-and γ-Lipotropins (C) α-and β-Endorphins(D) FSH
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 : Main metabolic end product of cholesterol: (A) Coprosterol (B) 5-pregnenolone (C) Bile acid (D) Glycine
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 : Cholesterol is a precursor in the biogenesis of (A) Vitamin A (B) Vitamin D (C) Vitamin E (D) None of these
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 : The major metabolite of progesterone is (A) Pregnenolone (B) Pregnanediol (C) Estradiol (D) Norethindrone
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 : Chlorpromazine therapy increases the secretion of the following hormone: A. Prolactin B. Gonadotropin C. Corticotropin D. Antidiuretic hormone
Last Answer : A. Prolactin
Description : The following hypothalamic regulatory hormone is not a peptide: A. Growth hormone release inhibitory hormone B. Prolactin release inhibitory hormone C. Gonadotropin releasing hormone D. Corticotropin releasing hormone (
Last Answer : B. Prolactin release inhibitory hormone
Description : Body water is regulated by the hormone: (A) Oxytocin (B) ACTH (C) FSH (D) Epinephrine
Description : Which of the following hormones is not involved in carbohydrate metabolism? (A) ACTH (B) Glucagon (C) Vasopressin (D) Growth hormone
Description : Gastric Secretion is regulated by the hormone: (A) Glucagon (B) Gastrin (C) Epinephrin (D) ACTH
Description : Proopiomelanocortin is the precussor of (A) ACTH (B) β-tropin (C) Endorphins (D) All of these
Description : Which of the following hormone is not under the control of ACTH? (A) Aldosterone (B) Cortisol (C) Corticosterone (D) Deoxycorticosterone
Description : Which one of the following is not liberated by the adenohypophysis? (A) Growth hormone (B) TSH (C) ACTH (D) Gonadotropin
Description : Secretion of androgens is increased by (A) LH (B) FSH (C) ACTH (D) Growth hormone
Description : Secretion of mineralcorticoids is increased by (A) ACTH (B) Angiotensin (C) Hypokalaemia (D) Hypernatraemia
Description : Acromegaly results from overproduction of (A) ACTH during childhood (B) TSH during adult life (C) Growth hormone during childhood (D) Growth hormone during adult life HORMONE METABOLISM 219
Description : Hormonal activity of ACTH is completely lost on removal of (A) 5 C-terminal amino acids (B) 10 C-terminal amino acids (C) 15 C-terminal amino acids (D) None of these
Description : ACTH is a polypeptide made up of (A) 39 amino acids (B) 41 amino acids (C) 51 amino acids (D) 84 amino acids
Description : All the following statements about ACTH are true except (A) It is a tropic hormone (B) Its target cells are located in adrenal cortex (C) Its receptors are located in the cell membrane (D) Its second messenger is inositol triphosphate
Description : A nonapeptide among the following is (A) Antidiuretic hormone (B) Insulin (C) ACTH (D) Thyrotropin releasing hormone
Description : Secretion of MSH is regulated by (A) Feedback mechanism (B) Melatonin (C) Hypothalamic hormones (D) ACTH HORMONE METABOLISM 217
Description : Cyclic AMP acts as the second messenger for all of the following except (A) Oxytocin (B) TSH (C) ACTH (D) FSH 216 MCQs IN BIOCHEMISTRY
Description : The production of progesterone by corpus luteum cell is stimulated by (A) LH (B) TSH (C) ACTH (D) MSH
Description : A hormone which cannot cross the blood brain barrier is (A) Epinephrine (B) Aldosterone (C) ACTH (D) TSH
Description : The circulating concentration of ACTH in plasma is (A) 0.05 mµ/100 ml (B) 0.1–2.0 mµ/100 ml (C) 2.5–3.5 mµ/100 ml (D) 3.0–5.0 mµ/100 ml
Description : ACTH induces rise in (A) Cyclic AMP (B) Cyclic GMP (C) Calcium (D) Magnesium
Description : Excessive secretion of ACTH causes (A) Cushing’s syndrome (B) Addison’s disease (C) Myxoedema (D) Thyrotoxicosis
Description : ACTH stimulates the secretion of (A) Glucocorticoids (B) Epinephrine (C) Thyroxine (D) Luteinizing hormone
Description : Biological activity of ACTH requires (A) 10-N-terminal amino acid (B) 24-N-terminal amino acid (C) 24-C-terminal amino acid (D) 15-C-terminal amino acid
Description : Adrenocorticotropic hormone (ACTH) is a single polypeptide containing (A) 25 amino acid (B) 39 amino acid (C) 49 amino acid (D) 52 amino acid 208 MCQs IN BIOCHEMISTRY
Description : The hormone activating the glycogen synthase activity is (A) Insulin (B) Glucagon (C) Epinephrine (D) ACTH
Description : Protein anabolism is stimulated by (A) ACTH (B) Testosterone (C) Glucagon (D) Epinephrine
Description : Which of the following hormones is not involved in carbohydrate metabolism? (A) Cortisol (B) ACTH (C) Glucogen (D) Vasopressin
Last Answer : D
Description : Reactivation of inactive liver phosphorylase is normally favoured by (A) Insulin (B) Epinephrine (C) ACTH (D) Glucagon
Description : Which of the following techniques would be most useful in the differential diagnosis between ectopic Cushing's syndrome and pituitary dependent Cushing's disease. 1) Urine free cortisol 2) ... Dexamethasone suppression test 3) ACTH concentrations 4) Inferior petrosal sinus sampling 5) CRF test
Last Answer : Answers-4 Inferior petrosal sinus sampling with an elevated central ACTH concentration compared with the peripheral value is the most valuable test in the differential diagnosis of either Cushing's disease or ectopic Cushing's syndrome. The other tests are far less useful in comparison.
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