15. Drugs

Question 1

Drug

Answer 1

A substance taken into the body that modifies or affects chemical reactions in the body.

Question 2

Antibiotic

Answer 2

A medical drug that kills bacteria by interfering with some of their important metabolic reactions.

Kill bacteria or stop them from reproducing.

Question 3

What pathogens do antibiotics affect?

Answer 3

Bacteria, not viruses.

Question 4

Different ways in which antibiotics respond to bacteria.

Answer 4

• Cause the bacterial cell membrane to break, killing the bacterial cell
• Prevent bacteria from making new cell walls, so the bacteria cannot reproduce or grow.

Question 5

Why do antibiotics not affect viruses?

Answer 5

• Viruses don’t carry out same processes + chemical reactions as bacterial cells.
• Don’t have cell membranes / cell walls –> Don’t reproduce by dividing.

This means that antibiotics cannot be used to attack viruses.

Question 6

Antibiotic resistance

Answer 6

When microorganisms, particularly bacteria, develop the ability to survive the delivery of commonly used antibiotics.

–> Antibiotics don’t work in treating the disease bc of the resistant bacteria.

Question 7

How does antibiotic resistance work?

Answer 7

• In any given population of bacteria –> some individuals are resistant to bacteria.
  –> (genetic material allows them to produce susbtances that counteract the effects of antibiotics)

1) Antibiotics adminestered.
2) Non-resistant bacteria dies/ Stops reproducing, but resistant bacteria survives.
3) Resistnat bacteria continues to grow/ reproduce until creating a new population.

Question 8

MRSA

Answer 8

Methicillin-resistant Staphlococcus aureus (bacteria which infects already sick people –> on skin/ in nostrils or throat), a strain of bacterium that is resistant to methicillin, an antibiotic.

Question 9

How to stop antibiotic resistance

Answer 9

• Only used antibiotics when essential.
• Never take antibiotics for a cold or flu.

Question 10

Methicillin

Answer 10

Semi-synthetic antibiotic related to penicillin.

Question 11

Penicillin

Answer 11

Antibiotic naturally produced by some moulds but now produced synthetically and used in the treatment of bacterial infections.

Question 12

Zone of inhibition

Answer 12

A circular area around the spot of the antibiotic in which the bacteria colonies do not grow