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 : What is the role of second messenger in hormone action? -Biology
Last Answer : answer:
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 : 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 : Which one of the following is not a secondary messenger in hormone action ?
Last Answer : Which one of the following is not a secondary messenger in hormone action ? A. Sodium B. cAMP C. cGMP D. Calcium
Description : Which one of the following is not a secondary messenger in hormone action? (a) cAMP (b) cGMP (c) Calcium (d) Sodium
Last Answer : d) Sodium
Description : The second messenger for many hormones is (A) ATP (B) cyclic AMP (C) cGMP (D) UTP HORMONE METABOLISM 227
Last Answer : Answer : B
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 : 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
Last Answer : Answer : D
Description : Hormone that bind to cell surface receptor and require the second messenger camp is (A) Antidiuretic hormone (B) Cholecystokinin (C) Calcitriol (D) Gastrin
Last Answer : Answer : A
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 : With regard to membrane receptors for hormones: a. they are often glycoproteins b. they are important for hormones made up of steroid c. those for insulin exhibit an intrinsic protein kinase activity d. glucagon uses calcium as a second messenger
Last Answer : they are often glycoproteins
Description : During mechanism of action of insulin, protein kinase C is activated by
Last Answer : During mechanism of action of insulin, protein kinase C is activated by A. `PIP_2` B. `IP_3` C. `DG ` D. `Ca^(2+)`
Description : Antibacterial agents can be classified with regard to their structure, mechanism of action, and activity pattern against various types of bacterial pathogens. Which of the following ... are both bacteriostatic d. Sulfonamides and trimethoprim act synergistically to inhibit purine synthesis
Last Answer : Answer: a, b, d Penicillins, cephalosporins, and monobactams possess a b-lactam ring of some type and act to bind bacterial division plate proteins, thus inhibiting cell wall ... act in different mechanisms to inhibit protein synthesis, therefore two agents in combination act synergistically
Description : The most important mechanism by which tetracycline antibiotics exert antiimicrobial action is (a) They chelate Ca2+ ions and alter permeability of bacterial cell membrane (b) They bind to 30S ribosomes ... peptide chain in the bacteria (d) They interfere with DNA mediated RNA synthesis in bacteria
Last Answer : Ans: B
Description : Trichloroacetic acid, a strong acid, has been used by dentists for chemical cautery of hypertrophic tissue and aphthous ulcers; its mechanism of action is, BOUCHERS P 194 A. Thermodynamic ... Activation of tissue enzymes C. Osmotic pressure D. Protein precipitation (PPT) E. Neutralization
Last Answer : D. Protein precipitation (PPT)
Description : The most important mechanism by which tetracycline antibiotics exert antimicrobial action is: A. They chelate Ca2+ ions and alter permeability of bacterial cell membrane B. They bind to 30S ribosomes ... peptide chain in the bacteria D. They interfere with DNA mediated RNA synthesis in bacteria
Last Answer : B. They bind to 30S ribosomes and inhibit bacterial protein synthesis
Description : Why second-messenger systems are required for peptide hormones? -Biology
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 : 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 : Secretion of MSH is regulated by (A) Feedback mechanism (B) Melatonin (C) Hypothalamic hormones (D) ACTH HORMONE METABOLISM 217
Last Answer : Answer : C
Description : What is the mechanism of activation of hormone sensitive lipase?
Last Answer : A cascade through adenyl cyclase, cyclic AMP and kinase.
Description : Mark the second messenger in case of heart in response to parasympathetic nervous system.
Last Answer : Mark the second messenger in case of heart in response to parasympathetic nervous system. A. cAMP B. cGMP C. `IP_3` D. `DG`
Description : All the following hormones use cAMP as a second messenger except (A) Estrogen (B) FSH (C) Luteinizing (D) Glucagon
Description : Hormonal stimulation of the formation of the second messenger inositol 1,4,5 triphosphate (IP3) quickly leads to the release of which other intracellular messenger? (A) cAMP (B) Prostaglandin (C) Calcinon (D) Leukotriene
Description : One of the following is not used as a second messenger by hormones: (A) mRNA (B) cAMP (C) Calcium ions (D) Myoinisotol 1, 4, 5 triphosphate
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 : Inositol triphosphate is the second messenger for (A) Gastrin (B) Cholecystokinin (C) Oxytocin (D) All of these
Description : Cyclic GMP acts as the second messenger for (A) Nerve growth factor (B) Atrial natriuretic factor (C) Epinephrine (D) Norepinephrine
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 : Dipalmitoyl lecithin acts as (A) Platelet activating factor (B) Second messenger for hormones (C) Lung surfactant (D) Anti-ketogenic compound
Description : Lock and Key mechanism of enzyme action? -Biology
Description : Induced fit mechanism of enzyme action -Biology
Description : What is the role of thyroid stimulating hormone? -Biology
Description : Role of plant hormone in fruit ripening? -Biology
Description : Which of the following statements about the role of the gut in shock and sepsis are true? A. Selective decontamination of the digestive tract with the use of oral antibiotics has been ... As compared with parenteral nutrition, enteral nutrition is associated with a reduction in septic morbidity.
Last Answer : Answer: BCD DISCUSSION: The gut has a vital role in the pathophysiology of shock. The splanchnic circulation is very vulnerable to the circulatory redistribution that occurs in shock, thus, gut ... , enteral feeding is more cost effective and is associated with a lower rate of septic morbidity
Description : The most important mechanism of bacterial resistance to an aminoglycoside antibiotic is (a) Plasmid mediated acquisition of aminoglycoside conjugating enzyme (b) Mutational acquisition of aminoglycoside ... affinity of ribosomal protein for the antibiotic (d) Mutational loss of porin channels
Last Answer : Ans: A
Description : The most important mechanism by which gram negative bacilli acquire chloramphenicol resistance is (a) Decreased permeability into the bacterial cell (b) Acquisition of a plasmid encoded ... bacterial ribosome for chloramphenicol (d) Switching over from ribosomal to mitochondrial protein synthesis
Description : Production of a human protein in bacteria by genetic engineering is possible because (a) the human chromosome can replicate in bacterial cell (b) the mechanism of gene regulation is identical in ... ) bacterial cell can carry out the RNA splicing reactions (d) the genetic code is universal.
Last Answer : (d) the genetic code is universal.
Description : The 1992 Nobel Prize for medicine was awarded to Edmond H. Fischer and Edwin J. Krebs for their work concerning (a) reversible protein phosphorylation as a biological regulation mechanism (b) ... (c) human genome project (d) drug designing involving inhibition of DNA synthesis of the pathogen.
Last Answer : (a) reversible protein phosphorylation as a biological regulation mechanism
Description : .Viruses possess (a) ribosomes to synthesize protein (b) organelle for its vital mechanism (c) either DNA or RNA (d) none of these.
Last Answer : (c) either DNA or RNA
Description : The most important mechanism by which gram negative bacilli acquire chloramphenicol resistance is: A. Decreased permeability into the bacterial cell B. Acquisition of a plasmid encoded ... the bacterial ribosome for chloramphenicol D. Switching over from ribosomal to mitochondrial protein synthesi
Last Answer : B. Acquisition of a plasmid encoded for chloramphenicol acetyl transferas
Description : Mammalian cells are not inhibited by low concentrations of tetracyclines that inhibit sensitive microorganisms because: A. Host cells lack active transport mechanism for tetracyclines B. Host cells actively pump out ... host cells has low affinity for tetracyclines D. Both A' and C' are correct
Last Answer : D. Both ‘A’ and ‘C’ are correct
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 : Which one of the following statements regarding a catalyst is not correct? A An enzyme is a catalyst that only binds certain substrates. B An enzyme is a protein that is a highly ... increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.
Last Answer : C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy.