3.1 - Antibiotics (Part 1)

Question 1

What is an antimicrobial?

Answer 1

A substance or agent that has the ability to kill or inhibit growth of microorganisms (bacteria, viruses, fungi, parasites).

Question 2

What is an antibiotic?

Answer 2

An antimicrobial that specifically targets bacteria (Are often naturally occuring)

Question 3

What is a bactericidal agent?

Answer 3

A drug that kills bacteria

Question 4

What is a bacteriostatic agent?

Answer 4

A drug that prevents the growth or organisms - relies on host mechanisms to eliminate the pathogen

Question 5

What is the spectrum of antibiotic activity?

Answer 5

Range of bacterial species susceptible to the effect of a drug - can be broad, intermediate, or narrow.

Question 6

How do Gram+ bacteria stain? Give an example of a kind of bacteria

Answer 6

Gram + bacteria are defined by a cell wall with a thick layer of peptidoglycan. So, they stain purple.
e.g. Staphylococcus aureus

Question 7

How do Gram- stain?

Answer 7

Have less peptidoglycan and two phospholipid bilayers. Do not gram stain.
e.g.,Pseudomonas aeruginosa

Question 8

What are the five mechanisms of antimicrobial action?

Answer 8

1. Inhibition of bacterial metabolic pathways
2. Inhibition of cell wall synthesis
3. Inhibition of protein synthesis
4. Inhibition of nucleic acid replication and transcription (DNA)
5. Disruption of plasma membrane