1.4 - breathing

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

Today's plan

1. Any HW questions?

2. 1.4 - Breathing

3. Function of the alveoli 

4. Chest vs. Abdominal breathing

Alveoli

The alveoli are located at the end of the bronchioles. 

This is where gas exchange (gaswisseling) happens.

The place where Oxygen goes to the blood and Carbon dioxide to the lungs. 

The alveoli are surrounded by tiny blood vessels (aderen), named the lung capillaries. 

Blood flowing to the alveoli is oxygen poor (zuurstof arm) and carbon dioxide rich ( CO2 rijk) (blue).

Blood flowing from the alveoli is oxygen rich (Zuurstof rijk) and carbon dioxide poor (CO2 arm) (red)

The walls of the lung capillaries and alveoli are extremely thin (1 cell layer).

The surface area (het oppervlakte)  of the alveoli is really big. This means gas exchange can happen at many places. 

Because of the thin walls and the big surface area, gas exchange can happen very fast!

(there are about 300-500 million alveoli's in your lungs)

Gas exchange 

1) Oxygen comes from the air we inhale into the alveoli -> Oxygen goes from alveoli through the wall into the blood of the lung capillary -> blood brings Oxygen to all the cells in the body. 

2) Blood brings Carbon dioxide from cells to the lungs -> Carbon dioxide goes from blood through the walls into the alveoli -> We breath out the Carbon dioxide.

The walls of the windpipe, bronchi, bronchioles and alveoli are covered with a mucus lining.

 

Cilia are constantly sweeping the mucus back up towards the pharyx where it is swallowed.

Chest breathing

Chest breathing

Abdominal breathing

TO DO

Read 1.4 Breathing

Qs 1 t/m 3, 5 t/m 8