How do microorganisms get into the body?
pathogens get into the body by penetrating one of the organisms interfaces with the environment. (interface - surface or boundary linking two systems (internal and external for instance) e.g. skin)

some of the interfaces of the body are designed for material exchange from the external and internal environment, so the lining around these areas are supplied with blood vessels, are moist and thin (therefore they are sticky) and they also have a large surface area.

Because these features make for easy entry for molecules they also make easy entry for pathogenic microorganisms.

common entry points include
- the gas exchange system - pathogens that cause influenza and tuberculosis.
-the digestive system - food and water carry pathogens into stomach and intestines via mouth. Cholera, typhoid and dysentery pathogens enter body through this way.

	Creado por mmutingwende2 hace casi 11 años

GCSE As level Biology Apunte sobre Cause of disease, creado por mmutingwende2 el 30/07/2013.