Topic 5 - Health, Disease & Medicine - antibiotics (5.16-5.20)

Question 1

Describe how antibiotics kill bacteria.

Answer 1

Antibiotics inhibit cell processes in the bacterium but not the host organism. For example, some antibiotics stop bacterial cell walls forming properly. This does not harm the host animal because animal cells do not have cell walls.

Question 2

How is boiling an aseptic technique

Answer 2

Kills the bacteria that isnt wanted

Question 3

Describe the process of developing new medicine.

Answer 3

• New medicines are discovered, eg by screening organisms to see if they produce antibiotics that kill bacteria. They are then developed through a series of stages.
• Antibiotics are then tested in the lab to make sure the medicine goes into cells without harming them, and damages pathogens inside the cell.
• Clinical trials are then used to find the optimum dose.

Question 4

Explain why new medicine is not tested on lots of people straight away

Answer 4

This is to make sure there are no harmful unforeseen side effects and to also make sure it works on people. It would also be unethical to give the medicine to lots of people before it was tested for safety too.

Question 5

How is flaming an aseptic technique

Answer 5

Pass an inoculation tube through a flame for sterilisation to kill unwanted microorganisms.

Question 6

How is incubation an aseptic technique

Answer 6

Reduces the risk of harmful bacteria growing

Question 7

How are lids an aseptic technique

Answer 7

To prevent air from getting into the Petri dish, the lid must be quickly removed and replaced when transferring bacteria to the agar using the inoculating loop.
This lid should be taped on and the dish should be stored upside down to prevent condensation from forming on the lid and then dripping onto the agar.

Question 8

How has drug discovery changed

Answer 8

Drugs were extracted from microorganisms and plants, now they are synthesised artificially by chemists.

Question 9

What is preclinical testing

Answer 9

Testing on human cells and tissues grown in the laboratory. Scientists can also test on animals in this stage

Question 10

What is clinical testing

Answer 10

Testing on healthy volunteers and potential patients