The respiratory system consists of several key parts divided into the upper and lower respiratory tracts, each with specific structures and functions:
Upper Respiratory Tract
- Nose and Nasal Cavity: Entry point for air, filters, warms, and moistens it.
- Sinuses: Air-filled spaces that help lighten the skull and produce mucus.
- Mouth: Alternative entry for air.
- Pharynx (Throat): Passageway for air from the nose/mouth to the larynx.
- Larynx (Voice Box): Contains vocal cords and routes air to the trachea; also involved in speaking
Lower Respiratory Tract
- Trachea (Windpipe): A tube supported by cartilage rings that conducts air to the lungs.
- Bronchi: The trachea splits into the right and left main bronchi, which enter the lungs and branch into smaller secondary (lobar) and tertiary (segmental) bronchi.
- Bronchioles: Smaller airways branching from the tertiary bronchi, lacking cartilage, leading air deeper into the lungs.
- Terminal Bronchioles: The smallest conducting airways.
- Respiratory Bronchioles, Alveolar Ducts, and Alveoli: Sites of gas exchange where oxygen enters the blood and carbon dioxide is expelled
Lungs
- Composed of lobes (right lung has three lobes; left lung has two lobes).
- Contain the bronchial tree and millions of alveoli.
- Surrounded by the pleura, a membrane that facilitates smooth lung movement during breathing
Additional Components
- Diaphragm: A muscle that aids in breathing by contracting and relaxing to change thoracic volume.
- Voice Box (Larynx): Also part of the upper tract, involved in sound production and protecting the airway during swallowing
In summary, the respiratory system includes the nose, mouth, pharynx, larynx, trachea, bronchi, bronchioles, alveoli, lungs, and the diaphragm, all working together to facilitate breathing and gas exchange
