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Question 1

Which of the following statements is false?

a) A bacterial cell is prokaryotic whereas an animal cell is eukaryotic.

b) A bacterial cell has a cell wall whereas an animal cell does not.

c) Bacterial and animal cells both have a well defined nucleus.

d) Bacteria may contain enzymes that are not present in animal cells.

Question 2

Which of the following is the general mechanism of action for erythromycin?

a) Inhibition of a metabolic enzyme.

b) Inhibition of cell wall synthesis.

c) Disruption of protein synthesis.

d) Inhibition of nucleic acid transcription and replication.

Question 3

The following general structure is representative of sulfonamides. Which of the following statements is true for active sulfonamides?

a) R¹ can be H or an alkyl group

b) R² must be hydrogen

c) The aromatic ring is essential

d) The sulfonamide functional group can be replaced with an ester

Question 4

Which of the following statements is true regarding the properties of benzylpenicillin?

a) It is a bacteriostatic agent.

b) It is active over a wide range of bacterial species.

c) It is resistant to β-lactamases.

d) Certain individuals may have an allergic response to it.

Question 5

What crucial feature of a penicillin is involved in its mechanism of action?

a) Carboxylic acid

b) β-lactam ring

c) Acyl side chain

d) Thiazolidine ring

Question 6

What reaction is catalysed by a β-lactamase enzyme?

a) The final cross-linking reaction to form the bacterial cell wall.

b) The hydrolysis of the acyl side chain from penicillin structures.

c) The hydrolysis of the four-membered ring present in penicillins.

d) The biosynthesis of the penicillin structure from the amino acids valine and cysteine.

Question 7

The following structure (methicillin) was an important penicillin that was introduced in the 1960s to counter the threat of penicillin-resistant strains of S. aureus.

Which of the following statements is true regarding the above structure?

a) There is no electron withdrawing group on the side chain, and so it is acid sensitive.

b) It can be taken orally.

c) It is more active than penicillin G.

d) It has a broader spectrum of activity compared to penicillin G.

Question 8

Which of the following statements is accurate in explaining why Gram negative bacteria are generally more resistant to penicillins than Gram positive bacteria?

a) Gram negative bacteria have a thicker cell wall

b) Gram negative bacteria have an outer hydrophilic membrane that acts as an extra barrier

c) Gram negative bacteria can concentrate β-lactamase enzymes in the periplasmic space

d) Gram negative bacteria produce smaller quantities of transpeptidase enzyme

Question 9

What role does the acetoxy group at the 3-position of cephalosporins have in enhancing antibacterial activity?

a) It acts as a steric shield and masks enzymatic attack at the β-lactam ring.

b) It acts as a good leaving group when the β-lactam ring is opened.

c) It takes part in a transesterification reaction with the carboxylic acid group at position 4.

d) It increases the reactivity of the β-lactam ring by neighbouring group participation.

Question 10

The following structure (cefalexin) is a first generation cephalosporin.

Which of the following statements is true for the methyl substituent at position 3?

a) It is a good leaving group.

b) It is generally good for activity.

c) It is good for oral activity.

d) It acts as a steric shield.

Question 11

What is the target for clavulanic acid?

a) The transpeptidase enzyme

b) L-ala racemase

c) β-lactamase

d) Penicillin acylase

Question 12

Which of the following antibiotics is a macrolide?

a) Chloramphenicol

b) Doxycycline

c) Erythromycin

d) Streptomycin

Question 13

Which of the following antibiotics is a tetracycline?

a) Chloramphenicol

b) Doxycycline

c) Erythromycin

d) Streptomycin

Question 14

Which of the following antibiotics is responsible for Gray Baby Syndrome?

a) Chloramphenicol

b) Doxycycline

c) Erythromycin

d) Streptomycin

Question 15

The following structure is a synthetic antibacterial agent.

To which group of compounds does the structure belong?

a) Aminoacridines

b) Aminoglycosides

c) Fluoroquinolones

d) Tetracyclines

Oxford University Press, Online Resource Centre, Chapter 19.

Chapter 19

Instructions

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

Question 11

Question 12

Question 13

Question 14

Question 15