The Breathing System (Cambridge (CIE) IGCSE Combined Science: Biology): Revision Note
Exam code: 0653
The breathing system
The breathing system includes the following parts:
the lungs
diaphragm
ribs
intercostal muscles
larynx
trachea
bronchi
bronchioles
alveoli and associated capillaries
Structures of the breathing system table
Structure | Description |
|---|---|
Ribs | Bone structure that protects internal organs such as the lungs |
Intercostal muscle | Muscles between the ribs which control their movement, causing inhalation and exhalation |
Diaphragm | Sheet of connective tissue and muscle at the bottom of the thorax that helps change the volume of the thorax to allow inhalation and exhalation |
Trachea | Windpipe that connects the mouth and nose to the bronchi, allowing air to pass into the lungs |
Larynx | Also known as the voice box; when air passes across here, we are able to make sounds |
Bronchi (singular: bronchus) | Large tubes branching off the trachea, with one for each lung |
Bronchioles | Bronchi split to form smaller tubes called bronchioles in the lungs, connected to alveoli |
Alveoli | Tiny air sacs where gas exchange takes place |
Examiner Tips and Tricks
You should be able to identify in diagrams and images the parts of the breathing system listed above, so make sure you study them.
Unlock more, it's free!
Join the 100,000+ Students that ❤️ Save My Exams
the (exam) results speak for themselves:
Was this revision note helpful?
