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Sourav PanNovember 14, 2024

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

Sourav Pan
Sourav PanNovember 14, 2024

Answered step-by-step

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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