Disease (Mechanism Of Infection)

Question 1

What is the definition of a disease?

Answer 1

A departure from positive health

Question 2

What is the difference between mutualism and commensalism in symbiosis?

Answer 2

Mutualism is where the relationship is beneficial to the host and the micro organism

Commensalism is where the relationship is only beneficial to the micro-organism

Question 3

What are the 5 stages of infection?

Answer 3

Incubation period

Prodromal phase

Invasive phase

Decline phase

Convalescence

Question 4

What factors determine the incubation period?

Answer 4

Number if parasites

Generation time

Virulence

Host resistance

Question 5

What happens in the prodromal phase of infection?

Answer 5

Body starts to show symptoms

Competition for supremacy in the body has begun

Body starts to try to expel infection. Coughing diarrhea etc

Question 6

What is the invasive phase?

Answer 6

Acute stage of disease where disease specific symptoms may appear

E.g. bullseye rash for lymes disease
Or cornflake scabs for impetigo

Question 7

What is the period of decline in a disease?

Answer 7

Body begins to overcome infection, symptoms may be most severe just before rapid recovery.

Question 8

What is convalescence?

Answer 8

Body functions return to normal although may still be contagious

Question 9

What is a dose when referred to disease causing organisms?

Answer 9

Number of organisms that must be taken into the body for disease to be established.

Question 10

What are biofilms?

Answer 10

Layers of polysaccharides that enclose bacteria and resist defences and drugs.