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Identify in diagrams and images the following parts of the breathing system: lungs, diaphragm, ribs, intercostal muscles, larynx, trachea, bronchi, bronchioles, alveoli and associated capillaries
Identify in diagrams and images the following parts of the breathing system: lungs, diaphragm, ribs, intercostal muscles, larynx, trachea, bronchi, bronchioles, alveoli and associated capillaries
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To identify the parts of the breathing system, here is a detailed overview of each component along with their functions:
Major Components of the Breathing System
1. Lungs
- Function: The primary organs for gas exchange, where oxygen is absorbed into the blood and carbon dioxide is expelled.
- Structure: Consists of lobes; the right lung has three lobes, while the left lung has two lobes to accommodate the heart.
2. Diaphragm
- Function: A dome-shaped muscle that separates the thoracic cavity from the abdominal cavity and plays a crucial role in breathing by contracting and relaxing to change the volume of the thoracic cavity.
- Action: When contracted, it moves downward, creating a vacuum that pulls air into the lungs.
3. Ribs
- Function: Protects the lungs and other thoracic organs; provides structural support for the chest cavity.
- Movement: Ribs move up and out during inhalation, assisting in lung expansion.
4. Intercostal Muscles
- Function: Located between the ribs, these muscles assist in expanding and contracting the chest cavity during breathing.
- Types:
- External Intercostals: Aid in inhalation by elevating the ribs.
- Internal Intercostals: Assist in forced exhalation by depressing the ribs.
5. Larynx
- Function: Known as the voice box, it houses the vocal cords and is responsible for sound production; it also protects the trachea against food aspiration.
- Location: Situated just below the pharynx and above the trachea.
6. Trachea
- Function: The windpipe that connects the larynx to the bronchi; it allows air to pass through to and from the lungs.
- Structure: Composed of C-shaped cartilaginous rings that keep it open.
7. Bronchi
- Function: The main passageways that branch from the trachea into each lung; they further divide into smaller bronchioles.
- Structure: Each bronchus enters a lung at a region called the hilum.
8. Bronchioles
- Function: Smaller branches of bronchi that lead to alveoli; they regulate airflow to different parts of the lungs.
- Structure: They become progressively smaller and are lined with smooth muscle.
9. Alveoli
- Function: Tiny air sacs where gas exchange occurs; oxygen diffuses into blood capillaries while carbon dioxide diffuses out.
- Structure: Each alveolus is surrounded by a network of capillaries, facilitating efficient gas exchange due to their thin walls.
10. Associated Capillaries
- Function: Tiny blood vessels that surround alveoli; they carry deoxygenated blood from the body to pick up oxygen and release carbon dioxide.
- Role in Gas Exchange: The close proximity of capillaries to alveoli allows for rapid diffusion of gases due to their thin walls.
Summary Table
Structure | Function |
---|---|
Lungs | Gas exchange (O2 in, CO2 out) |
Diaphragm | Main muscle for inhalation/exhalation |
Ribs | Protect thoracic organs; assist in breathing |
Intercostal Muscles | Expand/contract chest cavity during breathing |
Larynx | Sound production; protects trachea |
Trachea | Air passage between larynx and bronchi |
Bronchi | Main airways into lungs |
Bronchioles | Smaller airways leading to alveoli |
Alveoli | Site of gas exchange |
Associated Capillaries | Transport blood for gas exchange |
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