Description : A molecule of phosphorylase kinase is made up of (A) 4 subunits (B) 8 subunits (C) 12 subunits (D) 16 subunits
Last Answer : Answer : D
Description : Protein kinase C is activated by (A) Cyclic AMP (B) Cyclic GMP (C) Diacyl glycerol (D) Inositol triphosphate
Last Answer : Answer : C
Description : Which does NOT occur in a cell stimulated by a steroid hormone? A) The steroid hormone enters the cell by crossing the plasma membrane. B) The hormone binds to a receptor molecule in the ... activates certain genes. E) DNA is transcribed, mRNA is translated, and the result is protein synthesis.
Last Answer : C) The second messenger cyclic AMP is stimulated by the hormone-receptor complex. D) The hormone-receptor complex binds the chromatin and activates certain genes.
Description : The best understood intracellular messenger is cyclic AMP (cAMP). Which of the following statement(s) concerning this intracellular messenger is/are correct? a. Intracellular cyclic AMP is constantly ... of adenylate cyclase d. cAMP is the only cyclic nucleotide active as an intracellular messenger
Last Answer : Answer: a, b The prototypic intracellular messenger is cAMP. To function as a mediator, the concentration of cAMP must change rapidly. In resting cells, cAMP is continuously being degraded by ... produce cGMP. Intracellular calcium ions also serve as second messengers in a large number of cells
Description : One of the following enzymes does not change glycogen synthase a to b. (A) Glycogen synthase kinases 3, 4, 5 (B) Ca2+ calmodulin phosphorylase kinase (C) Ca2+ calmodulin dependent protein kinase (D) Glycogen phosphorylase a
Last Answer : D
Description : Insulin increases the activity of (A) Pyruvate kinase (B) Phosphorylase (C) Triacylglycerol kinase (D) Fructose 2, 6-bisphosphatase
Last Answer : Answer : A
Description : In the insulin receptor, tyrosine kinase domain is present in (A) α-Subunits (B) β-Subunits (C) γ-Subunits (D) δ-Subunits
Last Answer : Answer : B
Description : Atropine is contraindicated in (a) Cyclic AMP (b) Inositol trisphosphate (c) Diacyl glycerols (d) G protein
Last Answer : Ans: D
Description : Identify A, B and C in the diagramatic representation of the mechanism of hormone action. B A Response 1 C Physiological Responses Select the correct option from the following. (a) A-Steroid Hormone; B- ... ; C - Second Messenger (d) A-Protein Hormone; B-Cyclic AMP; C-Hormone-receptor Complex
Last Answer : (b) A-Protein Hormone; B-Receptor; C-Cyclic AMP
Description : Which is associated with a steroid hormone? A) cyclic AMP B) the second messenger system C) production of new proteins D) activation of proteins present in an inactive form E) binding of a protein to a surface receptor on the plasma membrane
Last Answer : C) production of new proteins
Description : The receptor transduction mechanism with the fastest time-course of response effectuation is: A. Adenylyl cyclase-cyclic AMP pathway B. Phospholipase C-IP3: DAG pathway C. Intrinsic ion channel operation D. Protein synthesis modulation
Last Answer : C. Intrinsic ion channel operation
Description : Phosphorylation of adenosine to AMP is catalysed by (A) Adenosine kinase (B) Deoxycytidine kinase (C) Adenylosuccinase (D) Adenylosuccinate synthetase
Description : Enhanced facultative reabsorption of water by Vasopressin is mediated by (A) Cyclic AMP (B) Ca++ (C) Cyclic GMP (D) Mg++
Description : All following are naturally occurring nucleotides except (A) Cyclic AMP (B) ATP (C) DNA (D) Inosine monophosphate
Description : Cyclic AMP can be formed from (A) AMP (B) ADP (C) ATP (D) All of these
Description : ADP ribosylation is the mode of action of (A) Cholera toxin (B) Acetyl choline (C) Muscerinic receptors (D) Cyclic AMP
Description : The second messenger for many hormones is (A) ATP (B) cyclic AMP (C) cGMP (D) UTP HORMONE METABOLISM 227
Description : The second messenger for glucocorticoids is (A) Cyclic AMP (B) Cyclic GMP (C) Inositol triphosphate (D) No second messenger is required
Description : Second messenger for glucagons is (A) Cyclic AMP (B) Diacylglycerol (C) Cyclic GMP (D) Inositol triphosphate
Description : The second messenger for PTH is (A) Cyclic AMP (B) Cyclic GMP (C) Diacylglycerol (D) Inositol triphosphate
Description : All the following statements about TSH are true except (A) It is a tropic hormone (B) It acts on para-follicular cells of thyroid glands (C) Its receptors are membrane-bound (D) Its second messenger is cyclic AMP
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 : Cyclic AMP acts as the second messenger for (A) ADH (B) Glucagon (C) Calcitonin (D) All of these
Description : All the following statements about steroid hormones are true except (A) They are hydrophobic (B) They require carriers to transport them in circulation (C) Their receptors are intracellular (D) They require cyclic AMP as second messenger
Description : ACTH induces rise in (A) Cyclic AMP (B) Cyclic GMP (C) Calcium (D) Magnesium
Description : Action of glycogen synthase is inhibited by (A) Insulin (B) Glucose (C) Mg2+ (D) Cyclic AMP
Description : Cyclic AMP is formed from ATP by the enzyme adenylate cyclase which is activated by the hormone: (A) Insulin (B) Epinephrine (C) Testosterone (D) Progesterone
Last Answer : B
Description : Glycogen synthetase activity is depressed by (A) Glucose (B) Insulin (C) Cyclic AMP (D) Fructokinase
Last Answer : C
Description : Lactose or its analogues act as positive regulators of lac operon by (A) Attaching to i gene and preventing its expression (B) Increasing the synthesis of catabolite gene activator protein (C) ... holoenzyme (D) Binding to repressor subunits so that the repressor cannot attach to the operator locus
Description : Activated phospholipase C acts on (A) Phosphatidyl inositol-4, 5-biphosphate (B) Inositol-1, 4, 5-triphosphate (C) Protein kinase C (D) Pl-3 kinase
Description : The protein IRS-1 is phosphorylated by (A) Protein kinase A (B) Protein kinase C (C) Tyrosine kinase activity of insulin receptor (D) Tyrosine kinase activity of IGF-1 receptor
Description : Vasoconstrictor effect of ADH is mediated by (A) cAMP (B) cGMP (C) Protein kinase C (D) Angiotensin II
Description : All the following statements about epidermal growth factor are true except (A) It is a protein (B) It possess quaternary structure (C) Its receptor is made up of a single polypeptide chain (D) Its receptor possesses tyrosine kinase domain
Description : Insulin decreases the activity of (A) cAMP dependent protein kinase (B) HMG CoA-reductas (C) Phosphodiesterase (D) Acetyl CoA-carboxylase
Description : Covalent modification of an enzyme generally requires a (A) Hormone (B) cAMP (C) Protein kinase (D) All of these
Description : Adipose tissue lacks (A) Hormone-sensitive lipase (B) Glycerol kinase (C) cAMP-dependent protein kinase (D) Glycerol-3-phosphate dehydrogenase
Description : The regulatory i gene of lac operon (A) Is inhibited by lacotse (B) Is inhibited by its own product, the repressor protein (C) Forms a regulatory protein which increases the expression of downstream structural genes (D) Is constitutively expressed
Description : Organic nitrates relax vascular smooth muscle by (a) Increasing intracellular cyclic AMP (b) Increasing intracellular cyclic GMP (c) Decreasing intracellular cyclic AMP (d) Both (b) and (c)
Last Answer : Ans: B
Description : The following are true about parathyroid hormone a. it is an 84 amino acid peptide hormone b. it increases calcium absorption from the gastrointestinal tract c. it acts on a cell surface receptor that increases intracellular cyclic AMP d. all above
Last Answer : all above
Description : Which of the following does not act interacellularly to produce physiologic effects a. Triiodothyronine b. Inositol triphosphate c. Aldosterone d. Cyclic AMP e. Doapamine
Last Answer : Doapamine
Description : How does steroid hormone influence the cellular activities? (a) Using aquaporin channels ‘as second messenger’ (b) Changing the permeability of the cell membrane (c) Binding to DNA and forming a gene-hormone complex (d) Activating cyclic AMP located on the cell membrane
Last Answer : (c) Binding to DNA and forming a gene-hormone complex
Description : Which statement is NOT true about non-steroid (peptide) hormones? A) They are derived from peptides, proteins, polypeptides, and derivatives of amino acids. B) They bind to receptors on the cell surface. ... They create an enzyme cascade effect. E) They enter the cell in order to have an effect.
Last Answer : E) They enter the cell in order to have an effect.
Description : Cyclic nucleotides exert the following action on salt transport across intestinal mucosal cells: A. Both cyclic AMP and cyclic GMP enhance Cland HCO3 - secretion B. Cyclic AMP enhances but cyclic GMP ... Cl- reabsorption D. Both cyclic AMP and cyclic GMP enhance Na+ and Cl- reabsorption
Last Answer : A. Both cyclic AMP and cyclic GMP enhance Cland HCO3 – secreti
Description : The following drug increases cyclic-AMP in platelets and inhibits their aggregation without altering levels of thromboxane A2 or prostacyclin: A. Aspirin B. Sulfinpyrazone C. Dipyridamole D. Abciximab
Last Answer : C. Dipyridamole
Description : Aspirin prolongs bleeding time by inhibiting the synthesis of: A. Clotting factors in liver B. Prostacyclin in vascular endothelium C. Cyclic AMP in platelets D. Thromboxane A2 in platelets
Last Answer : D. Thromboxane A2 in platelets
Description : Organic nitrates relax vascular smooth muscle by: A. Increasing intracellular cyclic GMP B. Increasing intracellular cyclic AMP C. Decreasing intracellular cyclic AMP D. Both ‘A’ and ‘C’ are correct
Last Answer : A. Increasing intracellular cyclic GMP
Description : 6.4 Several actions of growth hormone are exerted through the elaboration of: A. Cyclic AMP B. Cyclic GMP C. Somatostatin D. Insulin like growth factor-1
Last Answer : D. Insulin like growth factor-1
Description : All of the following subserve as intracellular second messengers in receptor mediated signal transduction except: A. Cyclic AMP B. Inositol trisphosphate C. Diacyl glycerols D. G proteins
Last Answer : D. G proteins
Description : The haemoglobin of a human fetus (a) has only 2 protein subunits instead of 4 (b) has a higher affinity for oxygen than that of an adult (c) has a lower affinity for oxygen than that of the adult (d) its affinity for oxygen is the same as that of an adult.
Last Answer : (b) has a higher affinity for oxygen than that of an adult