Description : Which of the following bacteria lack a cell wall and are therefore resistant to penicillin? A- Cyanobacteria B- Mycoplasmas C- Bdellovibrios D- Spirochetes
Last Answer : Mycoplasmas
Description : Mycoplasmas are different from the other prokaryotes by A- presence of chitin in cell walls B- presence of murrain in cell walls C- presence of proteins in cell wallsD- bsence of cell wall itself
Last Answer : bsence of cell wall itself
Description : Two major drawbacks to the use of ______ is allergies and beta- lactamases produced by resistant bacteria. a. Tetracycline b. Penicillin c. Cephalosporin d. Bacitracin
Last Answer : b. Penicillin
Description : Very slender bacteria like spirochetes are viewed by A Negative staining B Positive staining C Gram’s staining D Simple staining
Last Answer : A Negative staining
Description : Gram-positive bacteria, responsible for food poisoning, is/are A.Mycoplasmas B.Pseudomonas C.Clostridia D.all of these
Last Answer : C.Clostridia
Description : Gram-positive bacteria, responsible for food poisoning, is/ar A.Mycoplasmas B.Pseudomonas C.Clostridia D.all of these
Last Answer : .Clostridia
Description : Mycoplasmas, rickettsiae, and chlamydiae are A- .types of fungi B- small bacteria C- species of protozoa D- forms of viruses
Last Answer : small bacteria
Description : Cyanobacteria have A-a gram-positive cell wall B- a gram-negative cell wall C- Neither (a) nor (b) D-No cell wall
Last Answer : a gram-negative cell wall
Description : The phylum Cyanobacteria are unique because they _____. a. convert nitrogen to a useable form b. are poisonous c. photosynthesize d. have a waxy cell wall
Last Answer : c. photosynthesize
Description : Which of the following does not produce oxygen as a product of photosynthesis? A- A.Oak trees B.Purple sulfur bacteria C.Cyanobacteria D.Phytoplankton
Last Answer : Purple sulfur bacteria
Description : Genetic and biochemical similarities between contemporary cyanobacteria and eukaryoticchloroplasts are accepted to mean that A- .eukaryotes evolved from bacteria B- eukaryotes evolved from archaea C- . ... evolved in eukaryotes D- .cyanobacteria arose from chloroplasts which escaped from plant cells
Last Answer : eukaryotes evolved from archaea
Description : Select the wrong statement. (a) Bacterial cell wall is made up of peptidoglycan. (b) Pili and fimbriae are mainly involved in motility of bacterial cells. (c) Cyanobacteria lack flagellated cells. (d) Mycoplasma is a wall-less microorganism.
Last Answer : (b) Pili and fimbriae are mainly involved in motility of bacterial cells.
Description : Two drugs that affect cell wall synthesis are a. Erythromycin and penicillin. b. Vancomycin and cephalosporin. c. Tetracycline and polymyxin b. d. Chloramphenicol and streptomycin.
Last Answer : a. Erythromycin and penicillin.
Description : ________ is seen with periods of fever and chills when many spirochetes are present in the blood. a. Rabbit fever b. Lyme disease c. Relapsing fever d. The Plague
Last Answer : c. Relapsing fever
Description : The domain Archaea includes all the following groups except the a. Mycoplasmas. b. Extreme halophiles. c. Crenarchaeota. d. Euryarchaeota.
Last Answer : a. Mycoplasmas.
Description : Which one of the following pairs is incorrectly matched as to antibiotic and use? a. Penicillin-gram-positive bacteria b. Nystatin-fungi c. Tetracycline-viruses d. Griseofulvin-fungi
Last Answer : c. Tetracycline-viruses
Description : If a necrotizing soft tissue infection is considered, therapy mandates: a. Empiric administration of antibiotics active against gram-positive, gram-negative, and anaerobic bacteria b. Due to usually ... is mandatory d. The use of hyperbaric oxygen has been demonstrated to be clearly advantageous
Last Answer : Answer: a, c Identification of a necrotizing, soft tissue infection mandates immediate operative intervention with aggressive resection of all involved tissues and empiric ... remains without controlled trials demonstrating any additional benefits derived from hyperbaric oxygen therapy
Description : The bacterium Deinococcus radiodurans has been of interest to molecular biologists because a. it has the smallest known bacterial genome. b. it is a "living fossil" linking the Bacteria and Archaea. c. it has the largest known bacterial genome. d. it is very resistant to radiation damage.
Last Answer : d. it is very resistant to radiation damage.
Description : A medium would involve the addition of the antibiotic methicillin to identify methicillin-resistant bacteria. a. differential b. selective c. thioglycollate d. VBNC
Last Answer : b. selective
Description : Gram negative organisms are largely insensitive to benzyl penicillin because (a) They produce large quantities of penicillinase (b) They do not utilize D-alanine whose incorporation in the cell wall is ... lipoprotein-peptidoglycan multiplayer cell wall of gram-negative bacteria (d) Both (a) and (b)
Last Answer : Ans: C
Description : Gram negative organisms are largely insensitive to benzyl penicillin because: A. They produce large quantities of penicillinase B. They do not utilise D-alanine whose incorporation in the cell wall is inhibited ... multilayer cell wall of gram negative bacteria D. Both A' and B' are correct
Last Answer : . Benzyl penicillin is not able to penetrate deeper into the lipoprotein-peptidoglycan multilayer cell wall of gram negative bacteria
Description : The most likely explanation of differing sensitivities of different bacteria to various penicillins is: A. Differing susceptibilities of the various penicillins to β-lactamases produced by different ... into different bacteria D. Differing rates of cell wall synthesis by different bacteria
Last Answer : B. Differing affinities of penicillin binding proteins present in different bacteria towards various penicillins
Description : The cell wall of A.gram-positive bacteria are thicker than gram-negative bacteria B.gram-negative bacteria are thicker than gram-positive bacteria C.both have same thickness but composition is different D.none of these
Last Answer : A.gram-positive bacteria are thicker than gram-negative bacteria
Description : Which of the following is true about cell wall of gram-positive bacteria? A- It consists of multiple layers B- It is thicker than that associated with gram-negative bacteria C- It contains teichoic acids D- D.All of these
Last Answer : D.All of these
Description : The cell wall of A- gram-positive bacteria are thicker than gram-negative bacteria B- gram-negative bacteria are thicker than gram-positive bacteria C- both have same thickness but composition is different D- none of these
Last Answer : gram-positive bacteria are thicker than gram-negative bacteria
Description : Which of the following is true about cell wall of gram-positive bacteria? A-It consists of multiple layers B- It is thicker than that associated with gram-negative bacteria C- It contains teichoic acids D- All of these
Last Answer : All of these
Description : The unifying feature of the archaea that distinguishes them from the bacteria is A- habitats which are extreme environments with regard to acidity B- absence of a nuclear membrane temperature ... of a cell wall containing a characteristic outer membrane D- cytoplasmic ribosomes that are 70S
Last Answer : absence of a nuclear membrane temperature
Description : The gram-positive bacteria lack __________ structure/component? A.outer membrane B.murein C.teichoic acid D.plasma membrane
Last Answer : A.outer membrane
Description : A key energy compound in bacterial photosynthesis by cyanobacteria is ______ and a major end-product is ______. a. GTP; protein b. citrate; lactose c. glucose; chlorophyll d. ATP; glucose
Last Answer : c. glucose; chlorophyll
Description : Select the correct combination of the statements (i-iv) regarding the characteristics of certain organisms. (i) Methanogens are archaebacteria which produce methane in marshy areas. (ii) Nostoc is a filamentous blue-green alga which fixes ... iii) (c) (ii), (iii) and (iv) (d) (i), (ii) and (iv).
Last Answer : (d) (i), (ii) and (iv)
Description : Gram-negative bacteria would stain_________ with the Gram stain and have _______in the wall. a. orange-red; Teichoic acid b. orange-red; lipopolysaccharide c. purple; peptidoglycan d. purple; Teichoic acid
Last Answer : c. purple; peptidoglycan
Description : Which one of the following living organisms completely lacks a cell wall? (a) Cyanobacteria (b) Sea-fan (Gorgonia) (c) Saccharomyces (d) Blue-green algae
Last Answer : (b) Sea-fan (Gorgonia)
Description : Which of the following antibiotics work by targetting protein synthesis? a. Methicillin b. Chloramphenicol c. Penicillin d. Nystatin.
Last Answer : b. Chloramphenicol
Description : ____ is examples of drugs that are derived from the metabolism of microorganisms. a. Salvarsan b. Prontosil c. Penicillin d. A-C are correct
Last Answer : c. Penicillin
Description : Two cyclic polypeptide antibiotics are a. Vancomycin and streptomycin. b. Penicillin and cephalosporin. c. Bacitracin and polymyxins d. .gentamicin and chloramphenicol
Last Answer : c. Bacitracin and polymyxins
Description : The re-isolation and purification of penicillin was carried out by a. Waksman. b. Florey and Chain. c. Domagk. d. Fleming.
Last Answer : b. Florey and Chain.
Description : Ehrlich and Hata discovered that was used to treat a. Salvarsan; syphilis b. penicillin; surgical wounds c. Salvarsan; malaria. d. Prontosil; malaria
Last Answer : a. Salvarsan; syphilis
Description : Medications that can be used early in influenza are ____ and ____ because they inhibit the release of new virions. a. aspirin, decongestants b. Relenza, Tamiflu c. Penicillin, ampicillin d. AZT, ribivirin
Last Answer : b. Relenza, Tamiflu
Description : Though few in number, some drugs, such as _____, can be used to treat some viral infections. a. penicillin and ampicillin b. isoniazid and dapsone c. amantadine and acyclovir d. streptomycin and amphotericin
Last Answer : c. amantadine and acyclovir
Description : Penicillin resistance in staphylococci is acquired due to A.conjugation B.mutation C.transformation D.transduction
Last Answer : D.transduction
Description : An "International Unit" of penicillin activity established in 1944 is amount of penicillin equivalent to A.0.6 micrograms of crystalline penicillin G of about 98% purity B.0.6 micrograms of crystalline ... G of about 98% purity D.0.8 micrograms of crystalline penicillin G of about 90% purity
Last Answer : A.0.6 micrograms of crystalline penicillin G of about 98% purity
Description : Which of the following may be most likely to be missing from a gram-positive bacterium? A.Penicillin binding protein B.Peptidoglycan C.Lipopolysaccharide D.Phospholipid bilayer membrane
Last Answer : C.Lipopolysaccharide
Description : Penicillin resistance in staphylococci is acquired due to A- conjugation B- mutation C- transformation D- transduction
Last Answer : transduction
Description : The last step in synthesis of peptidoglycan is A- attachment of a peptide to muramic acid B- attaching two amino acids to form a cross-link C- attachment of a portion of peptidoglycan to a membrane lipid D- binding of penicillin to a membrane protein
Last Answer : attaching two amino acids to form a cross-link
Description : Methicillin resistant staphylococci do not respond to ß-lactam antibiotics because (a) They produce a ß-lactamase which destroys methicillin and related drugs (b) They elaborate an amidase which destroys ... low affinity for ß-lactam antibiotics (d) They are less permeable to ß-lactam antibiotics
Description : Spectinomycin is an aminoglycoside-like antibiotic indicated for the treatment of (a) Gram-negative bacillary septicemia (b) Tuberculosis (c) Penicillin-resistant gonococcal infections (d) Syphilis (e) Gram-negative meningitis due to susceptible organisms
Description : Select the semisynthetic penicillin which is not acid resistant: A. Phenoxymethyl penicillin B. Ampicillin C. Carbenicillin D. Cloxacillin
Last Answer : C. Carbenicillin
Description : Choose the semisynthetic penicillin which has an extended spectrum of activity against many gram negative bacilli, is acid resistant but not penicillinase resistant: A. Cloxacillin B. Amoxicillin C. Phenoxymethyl penicillin D. Piperacillin
Last Answer : B. Amoxicillin
Description : Methicillin resistant staphylococci do not respond to β-lactam antibiotics because: A. They produce a β-lactamase which destroys methicillin and related drugs B. They elaborate an amidase which destroys ... low affinity for β-lactam antibiotics D. They are less permeable to β-lactam antibiotics
Last Answer : C. They have acquired penicillin binding protein which has low affinity for β-lactam antibioti
Description : Cyclic phosphorylation is generally present in a. Cyanobacteria b. Algae c. Bacteria d. Plants
Last Answer : Ans: A