Controlling Disease

Page
1

Slide 1

Controlling Disease

We are an attractive dish for microbes!

Slide 2

Louis Pasteur

People thought that food went off because it was in contact with air. They thought:

Air + food microorganisms grow

Pasteur said that microbes come from microbes

He did som experiments to prove this -

Slide 3

Louis Pasteur

Slide 4

Pasteur’s Experiment

He poured some grape juice in 2 flasks

He then produced a ‘swan neck’ in the glass

He heated the flasks to boiling

One flask was left

The other had its neck broken off

Which went off? Why?

Slide 5

Pathogens

= microorganisms which cause disease

Drugs are used to help people with diseases

Painkillers – relieve the symptoms without curing the disease

Antibiotics – chemicals which kill bacteria, but not viruses. Viruses develop in cells and are hard to kill

Slide 6

Bacteria Drug Resistance

Bacteria in nature are varied. A few have the resistance to antibiotic

When the antibiotic is used there is a natural selection for the bacteria with the most drug resistance.

These survive and breed and become more common

Slide 7

Testing for Antibiotic Resistance in Bacteria

Clear of bacteria

Bacteria colonies growing near disc of antibiotic

Discs of different antibiotics

Slide 8

Antibiotic Resistance in Bacteria

Many strains of bacteria have resistance to antibiotic due to natural selection

So we need a range of antibiotics to fight disease with the best one for the job

To slow down more antibiotic resistance developing in pathogenic bacteria we need to avoid over using antibiotics