entry routes of pathogens

Question 1

4 main ways pathogens can enter the body

Answer 1

-broken skin
-respiratory system
-digestive system
-mucosal surfaces (lining of body cavities mouth, nose, genitals

Question 2

barriers to infection

Answer 2

skin: physical barrier to infection
-damaged skin leaves tissues underneath vulnerable to PATHOGENS
-blood clotting can prevent entry of pathogens when skin is damaged
-however blood clotting takes time so some pathogens may be able to enter before clot forms

-microorganisms in gut and skin:
-harmless microorganisms known as gut or skin flora
-compete with pathogens for resources, limiting their numbers and ability to infect the body

-stomach acid:
-HCl creates an acidic environment which is unfavourable to many pathogens
present on food and drink
-sometimes few of these pathogens will survive and enter intestines where they can infect gut wall cells

Lysozyme: secretions of mucosal surfaces like in tears, saliva and mucus contain the enzyme lysozyme
-this enzyme often damages bacterial cell walls causing them to lyse

mucus: can trap pathogens

sebaceous gland: produces sebum which kills bacteria and fungi