Sub Topic: HUMAN BREATHING MECHANISM
At the end of the lesson, student should be able to:
A. Human respiratory
4. In the lungs, the bronchus branches to form many smaller channels called bronchiole. Each bronchiole ends with
5. The function of the nasal cavity is to warm, moisten and filter fine particles like dust from the air that pass through it.
6. The trachea is a channel which branches into two. Each
branch is called bronchus
which enters the lungs.
8. Air is inhaled through the nasal cavity and taken through the trachea, bronchus, bronchiole and finally to the
9. The ribs protect the lungs and internal organs like the heart.
10. The diaphragm is a piece of muscle situated at the bottom of the lungs.
11. The intercostal muscles
are situated between the ribs. There are two types of intercostals muscles, i.e. the internal intercostal muscle and the external intercostal muscle. The intercostal muscles contract and relax to
12. Each alveoulus has a
very thin wall which is moist and contains a large networkof