2.1 Mechanical, Chemical and Microbiological barriers

Question 1

Mechanical

Answer 1

Epithelial cells joined by tight junctions:
-> Skin, Gut, Lungs, Eyes/Nose

Longitudinal flow of air or fluid
-> Skin + Gut

Movement of mucus by cillia
-> Lungs

Tears, Nasal Cillia
-> Eyes/Nose

Question 2

Chemical

Answer 2

Fatty acids
-> Skin

Low pH, Enzymes (pepsin)
-> Gut

Enzymes in Tears (lysozyme)
-> Eyes/Nose

Antibacterial peptides
-> Skin, Gut, Lungs

Question 3

Microbiological

Answer 3

Normal flora

-> Skin, Gut