The Respiratory System

Key Organs

Lungs: Paired organs located in the chest cavity that house the bronchi, bronchioles, and alveoli. The right lung has three lobes, and the left lung has two. They are referred to as the upper, middle, and lower lobes. Pulmo- is the root referencing lungs. For example, the pulmonary artery is the artery that connects the heart to the lungs.

Trachea (Windpipe): A tube that connects the larynx to the bronchi and allows air to pass through.

Larynx (Voice Box): Contains the vocal cords and is involve in breathing, sound production, and protecting the trachea against food aspiration.

Bronchi: Two main branches that lead from the trachea into each lung, further dividing into bronchioles. The Bronchioles lead to the alveoli.

Alveoli: Tiny air sacs where gas exchange occurs; oxygen enters the blood and carbon dioxide is removed.

Diaphragm: A large, dome-shaped muscle at the base of the lungs that plays a crucial role in breathing by contracting and relaxing to change the pressure in the chest cavity. The diaphragm is a voluntary and involuntary muscle.

Lungs

The primary function of the lungs is to facilitate the exchange of gases. Oxygen from the air we breathe enters the alveoli, tiny air sacs in the lungs. Here, oxygen diffuses through the thin walls of the alveoli and enters the surrounding capillaries, where it binds to hemoglobin in red blood cells.

Common diseases affecting lung function

Asthma: A chronic condition where the airways become inflamed and narrowed, leading to difficulty breathing, wheezing, and coughing. It is often triggered by allergens, exercise or stress.

Chronic Obstructive Pulmonary Disease (COPD): An umbrella term for chronic respiratory diseases like emphysema and chronic bronchitis. It is usually caused by long-term exposure to irritating gases or particulate matter, most often from cigarette smoke.

Pneumonia: An infection that inflames the air sacs in one or both lungs, which can fill with liquid or pus. It can be caused by bacteria, viruses, or fungi. Presents with symptoms like cough, fever, and difficulty breathing.