Description : Thyroid hormones are present in blood (A) In free form (B) In association with thyroxine binding globulin (TBG) (C) In association with thyroxine binding prealbumin (TBPA) (D) Mainly in association with TBG, partly in free form and sometimes in association with TBPA also
Last Answer : Answer : D
Description : The tyrosine residues per molecule of thyroglobulin is (A) 85 (B) 95 (C) 115 (D) 135
Last Answer : Answer : C
Description : Retinol and Retinol binding protein are bound with this protein: (A) Albumin (B) Prealbumin (C) α-globulin (D) β-globulin
Last Answer : Answer : B
Description : Retinol and retinol –binding protein (RBP) bound with this protein: (A) Albumin (B) Prealbumin (C) α2-globulin (D) β-globulin
Description : An enzyme required for the synthesis of thyroid hormones is (A) Iodinase (B) Deiodinase (C) Thyroperoxidase (D) Thyroxine synthetase
Description : In thyroxine, tyrosine residues are iodinated at positions: (A) 1 and 3 (B) 2 and 4 (C) 3 and 5 (D) 4 and 6
Description : The following are true: a. thyroxine is formed by iodination of tyrosine b. the ratio of T3 :T4 secreted by the thyroid gland is 1:5 c. about 99.5% of thyroxines is protein bound d. T3 is more active than T4
Last Answer : T3 is more active than T4
Description : The following are true about the thyroid hormone a. iodide ions enter the follicle cells by passive diffusion b .T4 and T3 bind to the receptors in nuclei c. thyroxine, once ... thyroglobulin until released d. a greater proportion of tri-iodothyronine is formed when iodine is deficient
Last Answer : T4 and T3 bind to the receptors in nuclei
Description : When thyroxine binding globulin and thyroxine binding pre-albumin are saturated with thyroxine, the excess hormone is transported by (A) Albumin (B) Gamma globulins (C) Transcortin (D) None of these
Last Answer : Answer : A
Description : Iodine is stored in (A) Thyroid gland as thyroglobulin (B) Liver (C) Intestine (D) Skin
Description : Thyrotropin exerts the following actions on the thyroid gland except: A. Increases vascularity B. Inhibits proteolysis of thyroglobulin C. Induces hyperplasia and hypertrophy D. Promotes iodide trappin
Last Answer : B. Inhibits proteolysis of thyroglobulin
Description : 16.18 Thyrotropin exerts the following actions on the thyroid gland except: A. Increases vascularity B. Inhibits proteolysis of thyroglobulin C. Induces hyperplasia and hypertrophy D. Promotes iodide trapping
Description : Tyrosine of thyroglobulin is acted upon by ________ to give mono and diiodo tyrosines. (A) Potassium Iodide (B) Iodine (C) Iodide I (D) Higher valency state of iodine (I+)
Description : Match the source gland with its respective hormone and function and select the correct option. Source Hormone Function gland (a) Anterior Oxytocin Contraction of uterus pituitary muscles during ... (c) Corpus Estrogen Supports pregnancy luteum (d) Thyroid Thyroxine Regulates blood calcium level
Last Answer : (b) Posterior Vasopressin Stimulates pituitary reabsorption of water in the distal tubules in the nephron
Description : Select the answer which correctly matches the endocrine gland with the hormone it secretes and its function/deficiency symptom. Endocrine Hormone Function/ gland Deficiency symptoms (a) ... child birth (d) Posterior Growth Oversecretion pituitary hormone stimulates (GH) abnormal growth
Last Answer : (a) Thyroid Thyroxine Lack of iodine gland in diet results in goitre
Description : The aim of iodine therapy before subtotal thyroidectomy in Grave’s disease is: A. To render the patient euthyroid B. To restore the iodine content of the thyroid gland C. To inhibit peripheral conversion of thyroxine into triiodothyronine D. To reduce friability and vascularity of the thyroid gland
Last Answer : D. To reduce friability and vascularity of the thyroid gland
Description : Choose the correct statement about carbimazole: A. It induces improvement in thyrotoxic symptoms afer 1-4 weeks therapy B. Control of thyrotoxic symptoms with carbimazole is accompanied by ... leads to thyroid escape' D. It mitigates thyrotoxic symptoms without lowering serum thyroxine levels
Last Answer : A. It induces improvement in thyrotoxic symptoms afer 1-4 weeks therap
Description : Edman’s reaction can be used to (A) Determine the number of tyrosine residues in a protein (B) Determine the number of aromatic amino acid residues in a protein (C) Determine the amino acid sequence of a protein (D) Hydrolyse the peptide bonds in a protein
Description : Which one of the following hormones is derived most completely from tyrosine? (A) Glucagon (B) Thyroxine (C) Insulin (D) Prostaglandins
Description : Thyroxine is derived from (A) Tyrosine (B) Tyranine (C) Taurine (D) Tryptaine
Description : T3 is (A) Thyroxine (B) Triodo thyronine (C) Triodo tyrosine (D) Reverse tri iodo thyronine
Description : Tyrosine is required for the synthesis of all of the following except (A) Melatonin (B) Epinephrine (C) Norepinephrine (D) Thyroxine 222 MCQs IN BIOCHEMISTRY
Description : Zinc finger motif is formed in some proteins by binding of zinc to (A) Two cysteine residues (B) Two histidine residues (C) Two arginine residues (D) Two cysteine and two histidine residues or two pairs of two cysteine residues each
Description : Progesterone is transported in blood by (A) Transcortin (B) Sex hormone binding globulin (C) Albumin (D) Testosterone estrogen binding globulin
Description : Testosterone is transported in blood by (A) Transcortin (B) Testosterone binding globulin (C) Testosterone estrogen binding globulin (D) Albumin
Description : A specific cortisol binding protein, transcortin is a (A) Albumin (B) α1-Globulin (C) α2-Globulin (D) β-Globulin
Description : Retinol is transported in blood bound to (A) Aporetinol binding protein (B) α2-Globulin (C) β-Globulin (D) Albumin
Description : Binding of thyroxine to its receptors (A) Activates Adenylate cyclase (B) Activates guanylate cyclase (C) Activates a stimulatory G-protein (D) Increases transcription
Description : Calcitomica is antagonist to (A) Serotonin (B) Thyroxine (C) Tri iodo thyronine (D) Para thyroid hormone
Description : Protein bound iodine is _________ bound to protein. (A) Iodine (B) Thyroid hormones (C) Thyroxine (D) Tri iodo thyronine
Description : Binding of insulin to its receptor activates (A) Adenylate cyclase (B) Guanylate cyclase (C) Phospholipase C (D) Tyrosine kinase
Description : Thyroperoxidase enzyme contains (A) Heme (B) Copper (C) Zinc (D) Magnesium
Description : An amino acid used for the synthesis of thyroid hormone is (A) Tyrosine (B) Tryptophan (C) Histidine (D) Proline
Description : Thyroid hormones are synthesized by the iodination of the amino acid: (A) Glycine (B) Phenylalanine (C) Alanine (D) Tyrosine
Description : All the following statements about phenylketonuria are correct except (A) Phenylalanine cannot be converted into tyrosine (B) Urinary excretion of phenylpyruvate and phenyllactate is increased (C) It ... diet (D) It leads to decreased synthesis of thyroid hormones, catecholamines and melanin
Description : Hormones thyroxine, adrenaline and the pigment melanin are formed from (a) tyrosine (b) proline (c) tryptophan (d) glycine.
Last Answer : (a) tyrosine
Description : The following thyroid inhibitor interferes with peripheral conversion of thyroxine to triiodothyronine: A. Propyl thiouracil B. Methimazole C. Carbimazole D. Radioactive iodine
Last Answer : A. Propyl thiouracil
Description : ntithyroid drugs exert the following action: A. Inhibit thyroxine synthesis B. Block the action of thyroxine on pituitary C. Block the action of TSH on thyroid D. Block the action of thyroxine on peripheral tissues
Last Answer : A. Inhibit thyroxine synthesis
Description : Antithyroid drugs exert the following action: A. Inhibit thyroxine synthesis B. Block the action of thyroxine on pituitary C. Block the action of TSH on thyroid D. Block the action of thyroxine on peripheral tissues
Last Answer : . Inhibit thyroxine synthesis
Description : Triiodothyronine is preferred over thyroxine in the treatment of: A. Endemic goiter B. Cretinism C. Papillary carcinoma of thyroid D. Myxoedema coma
Last Answer : D. Myxoedema coma
Description : Thyroxine therapy is indicated in the following conditions except: A. Euthyroid status with raised TSH level B. Diffuse nontoxic goiter C. Nonfunctional thyroid nodule D. Benign functioning thyroid nodule
Last Answer : C. Nonfunctional thyroid nodule
Description : Which of the following statement(s) is/are true concerning cell membrane receptors? a. The largest family of cell surface receptors are the G-protein-linked receptors b. Activities of the ... through the use adenylate cyclase d. Tyrosine kinase receptors are considered G-protein-linked receptors
Last Answer : Answer: a, c All water-soluble regulatory molecules bind to the cell surface receptor proteins. Binding of the appropriate ligand evokes an intracellular signal which usually regulates ... are adenylate cyclase, which converts ATP to cAMP, and the polyphosphoinositide-specific phospholipase C
Description : The percentage of inactive precursors (monoidotyrosine and diiodotyrosine) in thyroglobulin is (A) 30 (B) 40 (C) 50 (D) 70
Description : When iodine supplies are sufficient the T3 and T4 ratio in thyroglobulin is (A) 1 : 2 (B) 1 : 4 (C) 1 : 7 (D) 1 : 10
Description : Radioactive iodine uptake by thyroid gland is increased in (A) Endemic goitre (B) Hyperthyroidism (C) Myxoedema (D) Creatinism
Description : Radioactive iodine uptake by thyroid gland 24 hours of a test dose is (A) 1.5–15% of the test done (B) 15–20% of the test done (C) 20–40% of the test done (D) 50–70% of the test done
Description : Iodide uptake by thyroid gland is decreased by (A) Thicyanate (B) Thiouracil (C) Thiourea (D) Methimazole
Description : Parathyroid hormone (PTH) is synthesised in (A) Chief cells of parathyroid glands (B) Oxyphil cells of parathyroid glands (C) Para follicular cells of thyroid glands (D) Follicular cells of thyroid gland
Description : Thyroid gland takes up circulating iodine (A) By simple diffusion (B) By facilitated diffusion (C) By active uptake (D) In exchange for chloride
Description : Somatotropin is secreted by (A) Hypothalamus (B) Anterior pituitary (C) Posterior pituitary (D) Thyroid gland