Topic 5 - Fighting Disease

Question 1

What are some physical barriers that our body has to prevent pathogens entering?

Answer 1

The skin, if it gets damaged it clots quickly to keep microorganisms out.
Hairs and mucus in your nose trap particles that could contain pathogens.
Cells in your trachea and bronchi produce mucus that traps pathogens.

Question 2

What are cilia?

Answer 2

Hair like structures in the airways in the lungs that waft the mucus up to the back of the throat where it can be swallowed

Question 3

What are some chemical barriers the body has to prevent pathogen entry?

Answer 3

The stomach produces hydrochloric acid which kills most pathogens that are swallowed
The eyes produce lysozyme (in tears) which kills bacteria on the surface of the eye

Question 4

Why can antibiotics only be used to treat bacterial infections?

Answer 4

Because they inhibit cell processes in the bacterium but not the host organism