2.3 The Respiratory System

Question 0

What is released in breathing?

Answer 0

Carbon dioxide

Question 1

What is absorbed during breathing?

Answer 1

oxygen

Question 2

Lungs. What is the wind pipe called?

Answer 2

the trachea

Question 3

What do the rings of cartilage round the trachea and bronchi? (3)

Answer 3

structure and support

keep the trachea open and flexible

Question 4

What are the two branches below the trachea called?

Answer 4

bronchus singular or bronchi plural

Question 5

Why is mucus present in the trachea and bronchi?

Answer 5

to trap dirt of dust and prevent it from reaching the bronchioles and air sacs.

Question 6

What are cilia and why are they present in the trachea and bronchi?

Answer 6

Small hairs which wave in order to push mucus carrying dirt up out of the trachea and bronchi and into the oesophagus to be digested.

Question 7

What are the many branches of the bronchi called?

Answer 7

bronchioles

Question 8

What are attached at the ends of bronchioles?

Answer 8

alveoli (air sacs)

Question 9

What make the alveoli efficient gas exchange structures? (3)

Answer 9

large surface area
networks of capillaries (good blood supply)
thin walls

Question 10

How are gases exchanged between the alveoli and blood capillaries?

Answer 10

• O2 is diffused from high conc. in alveoli to low conc. in capillaries
• CO2 is diffused from high conc. in capillaries to low conc. in alveoli