Paper 1: Human Defeneces

Question 1

What are chemical defences that are produced do?

Answer 1

Kill pathogens / make them inactive

Question 2

What do physical barriers do?

Answer 2

Make it hard for pathogens to enter the body

Question 3

What are examples of chemical defences?

Answer 3

Lysozymes
Hydrochloric acid

Question 4

What does lysozymes do?

Answer 4

Kills bacteria by digesting their cell walls

Question 5

Where can you find lysozymes?

Answer 5

In tears, saliva and mucus

Question 6

What are examples of physical barriers?

Answer 6

Skin
Cilia
Mucus

Question 7

What does unbroken skin do?

Answer 7

Forms a protective barrier because it’s too thick for most pathogens to get through

Question 8

What does mucus and cilia do?

Answer 8

In lining of lungs and move in a wave like motion moving mucus and trapped pathogens out of the lungs towards the back of the throat where it is swallowed

Question 9

What does hydrochloric acid do?

Answer 9

Kills pathogens in food and drink