contribution to disease (Robert Koch, Louis Pasteur and John Snow

Question 1

What was the miasma theory?

Answer 1

a belief that diseases were caused by ‘poisonous’ gas or the vapour from organic rotting matter.

Question 2

How and who disproved the miasma theory?

Answer 2

John snow disproved the miasma theory through his navigation of a cholera outbreak. He found out that infectious microbes cause diseases which were in the water pump that people drank out of.

Question 3

What is spontaneous generation?

Answer 3

Spontaneous generation was the belief that microbes spontaneously generate for no particular reason. This theory is not being used in today’s modern scientific knowledge as it has been disapproved by Louis Pasteur

Question 4

Define pasteurisation?

Answer 4

pasteurisation - the process of keeping something sterile by heating to kill living microbes.

Question 5

What did the swan neck flash experiment prove?

Answer 5

• that microbes in the air caused spoiling in the broth

that it slows down the motion of air through the tube and particles present in the air like bacteria become trapped in moisture on its inner surface. thus is why, proves Pasteurs objective.

Question 6

How did Robert Koch contribute to the understanding of disease?

Answer 6

Developed agar plate practises (culturing)

Developed vaccine for human cholera

Identified tuberculosis bacterium

Question 7

List Koch’s postulates

Answer 7

1. The pathogen must be found in animals suffering from the disease but not healthy animals
2. The pathogen must be isolated from a diseased animal and grown in pure
   culture
3. The cultured pathogen should cause disease when introduced into a healthy animal
4. The pathogen must be re - isolated from experimentally infected animalThis proves that specific microbes causes specific infectious diseases

Question 8

Identify a limitation of Koch’s postulates

Answer 8

Some pathogens cannot be grown in pure culture in agar medium