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

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