midterm exam

• I. Glycolysis, also known as the glycolytic pathway, the Embden-Meyerhof pathway, and the Embden Meyerhof-Parnas pathway. II. A six-step biochemical pathway, involving nine separate biochemical reactions, each of which requires a specific enzyme

   The first statement is true and the second statement is false
• I. Krebs Cycle. 

  II. The pyruvic acid molecules produced during glycolysis are converted into acetyl-coenzyme A (acetyl-CoA) molecules, which then enter the Krebs cycle

  Both statements are true and related
• Nutrients. Every microbe needs nourishment. II. Protein synthesis requires nutrients, which can be obtained from other organic materials or from the surrounding atmosphere.

  The first statement is true and the second statement is false
• 1st Generation Cephalosporin Antibiotics  

  I.  Cephalothin

  II.  S. pyogenes (Gram positive bacteria)

  III.  Staphylococcus aureus

  B. All statements are true but not all related
• The First Antibiotics  I.  In 1928, Alexander Fleming, a Scottish bacteriologist, accidentally discovered the first antibiotic when he noticed that growth of contaminant Penicillium notatum mould colonies on his culture plates was inhibiting the growth of Staphylococcus bacteria.II.  Zidovudine (also known as azidothymidine [AZT])

  B. Both statements are true but not related
•  Which of the following types of culture media is selective and differential?

  MacConkey agar
• Which of the following scientists discovered penicillin?

  1. Alexander Fleming
• Which of the following terms or names has nothing to do with the use of two drugs simultaneously? 

  b. Salvarsan
• Which of the following processes does not involve bacteriophages?*

  d. transformation
• The process whereby naked DNA is absorbed into a bacterial cell is known as:

  transformation.
• Sterilization can be accomplished by use of:

  an autoclave.
• The combination of freezing and drying is known as:

  lyophilization
• It would be necessary to use a tuberculocidal agent to kill a particular species of:

  Mycobacterium.
• Proteins that must link up with a cofactor to function as an enzyme are called:

  apoenzymes
• _________ are also -lactam antibiotics and, like penicillin, are produced by moulds.

  Cephalosporins
• Multidrug therapy is always used when a patient is diagnosed as having:


  tuberculosis
• Which of the following characteristics do animals, fungi, and protozoa have in common?  

  They obtain their energy and carbon atoms from chemicals.
•  Multidrug-resistant M. tuberculosis (MDR-TB). These strains are resistant to the two most effective first-line therapeutic drugs________


  isoniazid and rifampin
•  Which of the following is least likely to be taken into consideration when deciding which antibiotic to prescribe for a patient?


  patient’s weight
• All the following antimicrobial agents work by inhibiting protein synthesis except:  

   imipenem.
•  Which of the following is not a common mechanism by which antifungal agents work?  

  by dissolving hyphae
• Agents having the suffix “-cidal” kill organisms, whereas agents having the suffix “-static” merely inhibit their growth and reproduction. 


  True
• Macrolides


  b. inhibit protein synthesis. They are considered bacteriostatic at lower doses and bactericidal at higher doses
•  Mechanisms of action of antimicrobial agents are as follows: I. Inhibition of cell wall synthesis II.  Damage to cell membranes III. Inhibition of nucleic acid synthesis (either DNA or RNA synthesis) IV. Inhibition of protein synthesis • Inhibition of enzyme activity

  All of the above
• The goal of medical asepsis is to kill __________, whereas the goal of surgical asepsis is to kill __________.

   pathogens . . . . . all microorganisms
• Which of the following is not a common mechanism by which antimicrobial agents kill or inhibit the growth of bacteria?

   destruction of capsules
• When placed into a hypertonic solution, a bacterial cell will: 

  c. shrink.
• Thermophiles are organisms that “love” high temperatures.Microbes that grow best at moderate temperatures are called mesophiles.   Psychrophiles are organisms that “love” cold temperatures. 

  True
• Acidophiles prefer acidic environments, whereas alkaliphiles prefer environments that are alkaline.

  True
• Which of the following is least likely to lead to drug resistance in bacteria?


   receiving a gene that codes for the production of a capsule
• Which of the following does (do) not occur in anaerobes  

  ectron transport chain
• The ideal antimicrobial agent should:I.  Kill or inhibit the growth of pathogensII.  Cause no damage to the host & Cause no allergic reaction in the hostIII.  Be stable when stored in solid or liquid formIV.  Remain in specific tissues in the body long enough to be effectiveV.  Kill the pathogens before they mutate and become resistant to it

  I, II, III, IV, V
•  Most ATP molecules are produced during which phase of aerobic respiration?

   electron transport chain
• All the following types of culture media are enriched and selective except 

  blood agar.
•  All the following antimicrobial agents work by inhibiting cell wall synthesis except:  

  chloramphenicol.
• CEPHALOSPORINE ANTIBIOTIC-THERAPEUTIC APPLICATION

  Proteus mirabilis -1st, 2nd and 3rd Generation Pseudomonas aeruginosa -3rd Generation Staphylococcus aureus - 1st Generation
• In the first step of the Krebs cycle, acetyl-CoA combines with (A) to produce (B) (a tricarboxylic acid); hence, the other names for the Krebs cycle—the citric acid cycle, the tricarboxylic acid cycle, and the TCA cycle. It is referred to as a cycle because at the end of the eight reactions, the biochemical pathway ends up back at its starting point—(C).

  oxaloacetate- A,Ccitric acid - B
• Glycolysis

  1. Six-carbon molecule of glucose is ultimately broken down into

  2. Produces very little energy—a net yield of only two molecules of ATP

  3. Takes place in the cytoplasm of both procaryotic and eucaryotic cells
• Glycolysis

  Can take place in either the presence or absence of oxygen; oxygen does not participate in this phase of aerobic respiration
• Pyruvate

  Also called pyruvic acid