Causes of disease

-microorganisms (single called organism that can only be seen under a microscope, many microorganisms mstay in the body permanently, some are beneficial for the body

-pathogens are microorganisms, that are NOT beneficial but cause disease. Through bacteria, fungi and viruses

-pathogens cause disease that cause malfunction of the body or mind by damaging the host's tissues and producing toxins

-pathogens have to get into the body and colonise it's tissue => infection; when symptoms occur => disease

-get into body through broken skin (cuts/animal bites) , gas exchange system, digestive system

TO PREVENT: mucous layer that forms sticky barrier that's hard to penetrate, enzymes that break down pathogens, stomach-acids that kill microorganisms