Page 20 - E-Science Prim.4 concept1 t.1 _2024-2025_Neat
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Organ Function
1- Nose
The first organ of the respiratory system
through which the air enters the body.
2-Pharynx A common cavity between the digestive
3- Trachea and respiratory systems.
It allows air to pass from nose to
trachea.
A tube passes the air to lungs.
It is branches inside the lungs into 2
tubes (Bronchi)
They allow air to enter the lungs.
4- Bronchi (One bronchus in each lung)
5- Alveoli Each is divided into bronchioles that end
in tiny air sacs “alveoli” surrounded by
blood vessels.
They have thin walls surrounded by
blood capillaries, where the exchange
of gases occurs.
The blood takes oxygen and gets rid of
carbon dioxide.
They fill up with air like 2 balloons.
6- Lungs Bronchi, bronchioles and alveoli are
inside it.
7- A large muscle at the base of ribs.
Diaphragm It has an important role in the
respiration process. “Breathing”
First Term 20