1st Line of Defence

Question 1

SKIN

Answer 1

• The cells of the epidermis are closely packed which forms the toughest barrier for invading organisms.
• Tough outer keratin, waterproof layer protects against chemicals, toxins etc

Question 2

MUCOUS MEMBRANE

Answer 2

• The mucous membrane line the entire GI tract, respiratory and genitourinary tract.
• Secretes a fluid (mucous) which helps provenly the tracts from drying out and traps microbes, pathogens so they can be swallowed or expelled.

Question 3

SALIVA

Answer 3

• Contains enzymes that breaks down cell wall of pathogens so it can be destroyed by phagocytosis.
• Washes away and dilute microbes

Question 4

MECHANICAL BARRIERS

Answer 4

• Expell pathogenss by Coughing, sneezing, diarrhoea,