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 and inhibit bacterial protein synthesis C. They bind to 50S ribosomes and interfere with translocation of the growing peptide chain in the bacteria D. They interfere with DNA mediated RNA synthesis in bacteria

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 and inhibit
bacterial protein synthesis
C. They bind to 50S ribosomes and interfere
with translocation of the growing peptide
chain in the bacteria
D. They interfere with DNA mediated RNA synthesis in bacteria
by

1 Answer

Answer :

B. They bind to 30S ribosomes and inhibit
bacterial protein synthesis
by

Related questions

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 and inhibit bacterial protein synthesis (c) They bind to 50S ribosomes and interfere with translocation of the growing peptide chain in the bacteria (d) They interfere with DNA mediated RNA synthesis in bacteria

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

Aminoglycoside antibiotics exert the following action(s) on sensitive bacteria: A. Induce synthesis of defective proteins B. Make bacterial cell membrane more leaky C. Augment their own carrier mediated entry into the bacteria D. All of the above

Description : Aminoglycoside antibiotics exert the following action(s) on sensitive bacteria: A. Induce synthesis of defective proteins B. Make bacterial cell membrane more leaky C. Augment their own carrier mediated entry into the bacteria D. All of the above

Last Answer : D. All of the above

Chloramphenicol inhibits bacterial protein synthesis by: A. Binding to 30S ribosome and inhibiting attachment of aminoacyl tRNA B. Binding to 50S ribosome and preventing peptide bond formation C. Binding to 50S ribosome and blocking translocation of peptide chain D. Binding to both 30S and 50S ribosome and inducing misreading of mRNA code

Description : Chloramphenicol inhibits bacterial protein synthesis by: A. Binding to 30S ribosome and inhibiting attachment of aminoacyl tRNA B. Binding to 50S ribosome and preventing peptide bond formation C. Binding to ... chain D. Binding to both 30S and 50S ribosome and inducing misreading of mRNA code

Last Answer : B. Binding to 50S ribosome and preventing peptide bond formation

Select the antibiotic which inhibits bacterial protein synthesis by interfering with translocation of elongating peptide chain from acceptor site back to the peptidyl site of the ribosome so that ribosome does not move along the mRNA and the peptide chain is prematurely terminated: A. Chloramphenicol B. Erythromycin C. Tetracycline D. Streptomycin

Description : Select the antibiotic which inhibits bacterial protein synthesis by interfering with translocation of elongating peptide chain from acceptor site back to the peptidyl site of the ribosome so that ... chain is prematurely terminated: A. Chloramphenicol B. Erythromycin C. Tetracycline D. Streptomycin

Last Answer : B. Erythromycin

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 statement(s) is/are true concerning antimicrobial classes? a. Penicillins and cephalosporins share the compound structure of a b-lactam ring which binds to bacterial division plate proteins b. Tetracyclines and macrolides such as erythromycin inhibit bacterial ribosomal activity and therefore protein synthesis c. Aminoglycosides act in a similar fashion to tetracyclines and therefore are both bacteriostatic d. Sulfonamides and trimethoprim act synergistically to inhibit purine synthesis

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

The mechanism of antibacterial action of tetracycline involves (a) Binding to a component of the 50S ribosomal subunit (b) Inhibition of translocase activity (c) Blockade of binding of aminoacyl – tRNA to bacterial ribosomes (d) Selective inhibition of ribosomal peptidyl transferases (e) Inhibition of DNA–dependent RNA polymerase

Description : The mechanism of antibacterial action of tetracycline involves (a) Binding to a component of the 50S ribosomal subunit (b) Inhibition of translocase activity (c) Blockade of binding of ... (d) Selective inhibition of ribosomal peptidyl transferases (e) Inhibition of DNA-dependent RNA polymerase

Last Answer : Ans: C

The most probable mechanism of action of imidazole antifungal drugs is: A. They bind to ergosterol in fungal cell membrane and make it leaky B. They interfere with ergosterol synthesis by fungi C. They interfere with fungal mitosis D. They block oxidative phosphorylation in fungi

Description : The most probable mechanism of action of imidazole antifungal drugs is: A. They bind to ergosterol in fungal cell membrane and make it leaky B. They interfere with ergosterol synthesis by fungi C. They interfere with fungal mitosis D. They block oxidative phosphorylation in fungi

Last Answer : B. They interfere with ergosterol synthesis by fungi

Bactericidal action of aminoglycoside antibiotics is due to: A. Inhibition of bacterial protein synthesis B. Alteration of bacterial cell membrane permeability C. Damage to bacterial cell wall D. Inhibition of bacterial oxidative metabolism

Description : Bactericidal action of aminoglycoside antibiotics is due to: A. Inhibition of bacterial protein synthesis B. Alteration of bacterial cell membrane permeability C. Damage to bacterial cell wall D. Inhibition of bacterial oxidative metabolism

Last Answer : B. Alteration of bacterial cell membrane permeability

Vinca alkaloids exert antitumor activity by: A. Activating topoisomerase II to cause breaks in DNA strands B. Crosslinking DNA strands C. Inhibiting DNA mediated RNA synthesis D. Inhibiting polymerization of tubulin to form intracellular microtubules

Description : Vinca alkaloids exert antitumor activity by: A. Activating topoisomerase II to cause breaks in DNA strands B. Crosslinking DNA strands C. Inhibiting DNA mediated RNA synthesis D. Inhibiting polymerization of tubulin to form intracellular microtubules

Last Answer : D. Inhibiting polymerization of tubulin to form intracellular microtubules

The primary mechanism underlying the resistance of gram-positive organisms to macrolide antibiotics is (a) Methylation of binding sites on the 50S ribosomal subunit (b) Formation of esterases that hydrolyze the lactone ring (c) Increased activity of efflux mechanisms (d) Formation of drug-inactivating acetyltranferases (e) Decreased drug permeability of the cytoplasmic membrane

Description : The primary mechanism underlying the resistance of gram-positive organisms to macrolide antibiotics is (a) Methylation of binding sites on the 50S ribosomal subunit (b) Formation of ... ) Formation of drug-inactivating acetyltranferases (e) Decreased drug permeability of the cytoplasmic membrane

Last Answer : Ans: A

Which binding is inhibited by pactamycin? A- Aminoacyl-tRNA to the A-site of 30S subunit B- Initiator-tRNA to 30S/40S initiation complexes C- Peptidyl t-RNA to the 50S subunit D- Formation of peptide bond in P site

Description : Which binding is inhibited by pactamycin? A- Aminoacyl-tRNA to the A-site of 30S subunit B- Initiator-tRNA to 30S/40S initiation complexes C- Peptidyl t-RNA to the 50S subunit D- Formation of peptide bond in P site

Last Answer : Initiator-tRNA to 30S/40S initiation complexes

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 for chloramphenicol acetyl transferase C. Lowered affinity of the bacterial ribosome for chloramphenicol D. Switching over from ribosomal to mitochondrial protein synthesi

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

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

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

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

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

The antiviral action of amantadine is exerted through: A. Interaction with the viral M2 protein B. Interaction with a virus directed thymidine kinase C. Inhibition of a viral protease enzyme D. Inhibition of viral RNA mediated DNA synthesi

Description : The antiviral action of amantadine is exerted through: A. Interaction with the viral M2 protein B. Interaction with a virus directed thymidine kinase C. Inhibition of a viral protease enzyme D. Inhibition of viral RNA mediated DNA synthesi

Last Answer : A. Interaction with the viral M2 protein

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 for chloramphenicol acetyl transferase (c) Lowered affinity of the bacterial ribosome for chloramphenicol (d) Switching over from ribosomal to mitochondrial protein synthesis

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

Last Answer : Ans: B

Indicate the attribute that is common to both polymyxin B and bacitracin: A. Both are active against gram negative bacteria B. Both are too toxic for systemic use C. Both act by inhibiting bacterial cell wall synthesis D. Both a

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Methylxanthines exert the following action(s) at cellular/molecular level: A. Intracellular release of Ca2+ B. Antagonism of adenosine C. Inhibition of phosphodiesterase D. All of the above

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Last Answer : D. All of the above

The mode of action of polymyxin is to A- inhibit protein synthesis B- inhibit DNA synthesis C- injury to the plasma membrane D- inhibit folic acid synthesis

Description : The mode of action of polymyxin is to A- inhibit protein synthesis B- inhibit DNA synthesis C- injury to the plasma membrane D- inhibit folic acid synthesis

Last Answer : injury to the plasma membrane

he primary mechanism by which heparin prevents coagulation of blood is: A. Direct inhibition of prothrombin to thrombin conversion B. Facilitation of antithrombin III mediated inhibition of factor Xa and thrombin C. Activation of antithrombin III to inhibit factors IX and XI D. Inhibition of factors XIIa and XIIIa

Description : he primary mechanism by which heparin prevents coagulation of blood is: A. Direct inhibition of prothrombin to thrombin conversion B. Facilitation of antithrombin III mediated inhibition of factor Xa and ... of antithrombin III to inhibit factors IX and XI D. Inhibition of factors XIIa and XIIIa

Last Answer : B. Facilitation of antithrombin III mediated inhibition of factor Xa and thrombi

The polyene antibiotics act by: A. Inhibiting fungal cytochrome P450 enzyme B. Binding to ergosterol and creating micropores in fungal cell membrane C. Inhibiting fungal DNA synthesis D. Disorienting microtubules in fungal cells

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Last Answer : B. Binding to ergosterol and creating micropores in fungal cell membrane

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 hydrolysing enzyme C. Mutation reducing affinity of ribosomal protein for the antibiotic D. Mutational loss of porin channels

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Last Answer : A. Plasmid mediated acquisition of aminoglycoside conjugating enzyme

Insulin increases the permeability of glucose across the plasma membrane of muscle cells by (A) Acting on adenylate cycle (B) By loosening the integrity of the membrane (C) Through Ca2+ ions (D) By membrane cruting the hexose carries of intracellular organelles and making them fuse with the plasma membrane

Description : Insulin increases the permeability of glucose across the plasma membrane of muscle cells by (A) Acting on adenylate cycle (B) By loosening the integrity of the membrane (C) Through Ca2 ... membrane cruting the hexose carries of intracellular organelles and making them fuse with the plasma membrane

Last Answer : Answer : D

What is true of Quinupristin-Dalfopristin: A. It is a synergistic combination of two similar antibiotics B. It acts by inhibiting bacterial protein synthesis C. It is active against most resistant coccal infections D. All of the above are correct

Description : What is true of Quinupristin-Dalfopristin: A. It is a synergistic combination of two similar antibiotics B. It acts by inhibiting bacterial protein synthesis C. It is active against most resistant coccal infections D. All of the above are correct

Last Answer : D. All of the above are correct

Select the class of antibiotics which act by interfering with bacterial protein synthesis, but are bactericidal: A. Tetracyclines B. Aminoglycosides C. Macrolides D. Lincosamides

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Last Answer : B. Aminoglycosides

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 shown to reduce nosocomial pneumonias and to improve mortality rates. B. Enteral nutrition, as compared with parenteral nutrition, preserves the villus architecture of the gut. C. Gut dysfunction may be an effect of shock, but it may also contribute to the development of MODS by the mechanism of bacterial translocation. D. As compared with parenteral nutrition, enteral nutrition is associated with a reduction in septic morbidity.

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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

Penicillins interfere with bacterial cell wall synthesis by: A. Inhibiting synthesis of N-acetyl muramic acid pentapeptide B. Inhibiting conjugation between N-acetyl muramic acid and N-acetyl glucosamine C. Inhibiting transpeptidases and carboxypeptidases which cross link the peptidoglycan residues D. Counterfeiting for D-alanine in the bacterial cell wall

Description : Penicillins interfere with bacterial cell wall synthesis by: A. Inhibiting synthesis of N-acetyl muramic acid pentapeptide B. Inhibiting conjugation between N-acetyl muramic acid and N-acetyl ... cross link the peptidoglycan residues D. Counterfeiting for D-alanine in the bacterial cell wall

Last Answer : C. Inhibiting transpeptidases and carboxypeptidases which cross link the peptidoglycan residues

The following is true of selegiline: A. It does not exert antiparkinsonian action unless combined with levodopa B. It overcomes the ‘on-off ’ effect in levodopa treated advanced parkinsonian patients C. It retards the progression of Parkinson's disease D. At doses used in parkinsonism it does not interfere with peripheral metabolism of dietary amines

Description : The following is true of selegiline: A. It does not exert antiparkinsonian action unless combined with levodopa B. It overcomes the on-off ' effect in levodopa treated advanced parkinsonian ... D. At doses used in parkinsonism it does not interfere with peripheral metabolism of dietary amines

Last Answer : . At doses used in parkinsonism it does not interfere with peripheral metabolism of dietary amines

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 humans and bacteria (c) bacterial cell can carry out the RNA splicing reactions (d) the genetic code is universal.

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.

Select the correct statement about benzodiazepines (BZDs): A. All BZDs facilitate GABA mediated Cl¯ influx into neurones B. Different BZDs exert the same degrees of hypnotic, anxiolytic and anticonvulsant actions C. The BZD receptor is homogeneous at all neuronal sites D. The muscle relaxant action of BZDs is not blocked by flumazenil

Description : Select the correct statement about benzodiazepines (BZDs): A. All BZDs facilitate GABA mediated Cl¯ influx into neurones B. Different BZDs exert the same degrees of hypnotic, anxiolytic and anticonvulsant ... at all neuronal sites D. The muscle relaxant action of BZDs is not blocked by flumazenil

Last Answer : A. All BZDs facilitate GABA mediated Cl¯ influx into neurones

What are the Svedberg values for the subunits of the 70S ribosomes of E. colli? A- 40S and 30S B- 50S and 20S C- 50S and 30S D- .40S and 20S

Description : What are the Svedberg values for the subunits of the 70S ribosomes of E. colli? A- 40S and 30S B- 50S and 20S C- 50S and 30S D- .40S and 20S

Last Answer : 50S and 30S

Under certain circumstances, the gut may become a source of sepsis and serve as the motor of systemic inflammatory response syndrome. Microbial translocation is the process by which microorganisms migrate across the mucosal barrier to invade the host. Which of the following mechanisms can promote bacterial translocation? a. An increased number of gut bacteria b. Altered intestinal mucosal permeability c. Decreased host defense mechanisms d. Lack of enteral feeding

Description : Under certain circumstances, the gut may become a source of sepsis and serve as the motor of systemic inflammatory response syndrome. Microbial translocation is the process by which microorganisms ... intestinal mucosal permeability c. Decreased host defense mechanisms d. Lack of enteral feeding

Last Answer : Answer: a, b, c, d 99 Translocation is promoted in three general ways: 1) altered permeability of the intestinal mucosa as caused by shock, sepsis, distant injury, or cell toxins; 2) ... trauma patient d. Fifty percent of non-nitrogen caloric requirements should be provided in the form of fat

By which of the following means antifungal chemotherapeutic agents may affect fungi? A- Interfere with nuclear division by preventing the aggregation of microtubules needed for mitosis B- Interfere with normal nucleic acid synthesisInterfere with ergosterol biosynthesis and thus alter the structure of the cytoplasmic C- membrane as well as the function of several membrane-bound enzymes like thoseinvolved in nutrient transport and chitin synthesis D- all of these

Description : By which of the following means antifungal chemotherapeutic agents may affect fungi? A- Interfere with nuclear division by preventing the aggregation of microtubules needed for mitosis B- ... membrane-bound enzymes like thoseinvolved in nutrient transport and chitin synthesis D- all of these

Last Answer : all of these

Actions of 5-HT2 receptor activation are primarily mediated by: A. Increased membrane permeability to Na+ ions B. Increased formation of cAMP C. Activation of guanylyl cyclase D. Generation of inositol trisphosphate and diacyl glycerols

Description : Actions of 5-HT2 receptor activation are primarily mediated by: A. Increased membrane permeability to Na+ ions B. Increased formation of cAMP C. Activation of guanylyl cyclase D. Generation of inositol trisphosphate and diacyl glycerols

Last Answer : D. Generation of inositol trisphosphate and diacyl glycerols

.Viruses possess (a) ribosomes to synthesize protein ((c) either DNA or RNA (d) none of these.b) organelle for its vital 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

The most probable mechanism of anticonvulsant action of phenytoin is: A. Facilitation of GABAergic inhibitory transmission B. Hyperpolarization of neurones C. Interaction with Ca2+ channels to promote Ca2+ influx D. Prolongation of voltage sensitive neuronal Na+ channel inactivation

Description : The most probable mechanism of anticonvulsant action of phenytoin is: A. Facilitation of GABAergic inhibitory transmission B. Hyperpolarization of neurones C. Interaction with Ca2+ channels to promote Ca2+ influx D. Prolongation of voltage sensitive neuronal Na+ channel inactivation

Last Answer : D. Prolongation of voltage sensitive neuronal Na+ channel inactivation

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 hydrolyzing enzyme (c) Mutation reducing affinity of ribosomal protein for the antibiotic (d) Mutational loss of porin channels

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

Which of the following statement(s) is/are true concerning translation of the mRNA message to protein synthesis? a. An adaptor molecule, tRNA, recognizes specific nucleic acid bases and unites them with specific amino acids b. Covalent attachment of tRNA to amino acids is energy dependent c. The formation of a peptide bond between the growing peptide chain and the free amino acid occurs in the free cytoplasm d. Complete protein synthesis takes hours

Description : Which of the following statement(s) is/are true concerning translation of the mRNA message to protein synthesis? a. An adaptor molecule, tRNA, recognizes specific nucleic acid bases and unites them ... and the free amino acid occurs in the free cytoplasm d. Complete protein synthesis takes hours

Last Answer : Answer: a, b The synthesis of protein involves conversion from a four-letter nucleotide language to one of 20 chemically distinct amino acids. This process is referred to as ... translation and be moving down the mRNA molecules simultaneously, thus increasing the rate of protein synthesis

Vancomycin inhibits _____________ synthesis. a. protein b. DNA c. bacterial cell wall d. RNA

Description : Vancomycin inhibits _____________ synthesis. a. protein b. DNA c. bacterial cell wall d. RNA

Last Answer : c. bacterial cell wall

The main reason why antibodies could not solve all the problems of bacteria mediated disease is (a) decreased efficiency of the immune system (b) insensitivity of the individual following prolonged exposure to antibiotics (c) development of mutant strains resistant to antibodies (d) inactivation of antibiotics by bacterial enzymes.

Description : The main reason why antibodies could not solve all the problems of bacteria mediated disease is (a) decreased efficiency of the immune system (b) insensitivity of the individual ... development of mutant strains resistant to antibodies (d) inactivation of antibiotics by bacterial enzymes.

Last Answer : (c) development of mutant strains resistant to antibodies

The following is true of vancomycin except: A. It is a bactericidal antibiotic active primarily against gram positive bacteria B. It acts by inhibiting bacterial protein synthesis C. It is an alternative to penicillin for enterococcal endocarditis D. It can cause deafness as a dose related toxicity

Description : The following is true of vancomycin except: A. It is a bactericidal antibiotic active primarily against gram positive bacteria B. It acts by inhibiting bacterial protein synthesis C. It is an alternative to penicillin for enterococcal endocarditis D. It can cause deafness as a dose related toxicity

Last Answer : B. It acts by inhibiting bacterial protein synthesis

The vasopressin action(s) mediated by V2 receptors include(s): A. Increased water permeability of collecting duct cells B. Increased urea permeability of collecting duct cells C. Vasoconstriction D. Both 'A' and 'B

Description : The vasopressin action(s) mediated by V2 receptors include(s): A. Increased water permeability of collecting duct cells B. Increased urea permeability of collecting duct cells C. Vasoconstriction D. Both 'A' and 'B

Last Answer : D. Both 'A' and 'B

Sodium valproate has been shown to: A. Prolong neuronal Na+ channel inactivation B. Attenuate ‘T’ type Ca2+ current in neurones C. Inhibit degradation of GABA by GABA-transaminase D. All of the above

Description : Sodium valproate has been shown to: A. Prolong neuronal Na+ channel inactivation B. Attenuate ‘T’ type Ca2+ current in neurones C. Inhibit degradation of GABA by GABA-transaminase D. All of the above

Last Answer : D. All of the above

Erythromycin acts on ribosomes and inhibit (A) Formation of initiation complex (B) Binding of aminoacyl tRNA (C) Peptidyl transferase activity (D) Translocation

Description : Erythromycin acts on ribosomes and inhibit (A) Formation of initiation complex (B) Binding of aminoacyl tRNA (C) Peptidyl transferase activity (D) Translocation

Last Answer : Answer : D

The sulfonamides interfere with bacterial metabolism by a. blocking cell wall synthesis. b. disrupting folic acid metabolism. c. reacting with bacterial cell membranes. d. inhibiting DNA replication.

Description : The sulfonamides interfere with bacterial metabolism by a. blocking cell wall synthesis. b. disrupting folic acid metabolism. c. reacting with bacterial cell membranes. d. inhibiting DNA replication.

Last Answer : b. disrupting folic acid metabolism.

Choose the correct statement about ticlopidine: A. It blocks GPIIb/IIIa receptors on platelet membrane B. It prevents ADP mediated platelet adenylylcyclase inhibition C. It inhibits thromboxane A2 synthesis in platelets D. It does not prolong bleeding time

Description : Choose the correct statement about ticlopidine: A. It blocks GPIIb/IIIa receptors on platelet membrane B. It prevents ADP mediated platelet adenylylcyclase inhibition C. It inhibits thromboxane A2 synthesis in platelets D. It does not prolong bleeding time

Last Answer : B. It prevents ADP mediated platelet adenylylcyclase inhibition

The antibacterial action of aminoglycoside antibiotics is characterized by: A. Concentration dependent rate of bacterial cell killing B. Concentration dependent prolonged postantibiotic effect C. More pronounced bactericidal effect in anaerobic medium D. Both 'A' and 'B' are correct

Description : The antibacterial action of aminoglycoside antibiotics is characterized by: A. Concentration dependent rate of bacterial cell killing B. Concentration dependent prolonged postantibiotic effect C. More pronounced bactericidal effect in anaerobic medium D. Both 'A' and 'B' are correct

Last Answer : D. Both 'A' and 'B' are correct

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 tetracyclines C. Protein synthesizing apparatus of host cells has low affinity for tetracyclines D. Both ‘A’ and ‘C’ are correct

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

Antimicrobial treatment does not alter the course of the following diarrhoeas except: A. Mild enterotoxigenic E.coli diarrhoea B. Campylobacter diarrhoea C. Coeliac disease diarrhoea D. Food poisoning diarrhoea

Description : Antimicrobial treatment does not alter the course of the following diarrhoeas except: A. Mild enterotoxigenic E.coli diarrhoea B. Campylobacter diarrhoea C. Coeliac disease diarrhoea D. Food poisoning diarrhoea

Last Answer : B. Campylobacter diarrhoea

Choose the antimicrobial which acts by interfering with DNA function in the bacteria: A. Chloramphenicol B. Ciprofloxacin C. Streptomycin D. Vancomycin

Description : Choose the antimicrobial which acts by interfering with DNA function in the bacteria: A. Chloramphenicol B. Ciprofloxacin C. Streptomycin D. Vancomycin

Last Answer : B. Ciprofloxacin