Respiratory System Overview

Study Notes

The respiratory system is crucial for breathing in oxygen and breathing out carbon dioxide.
It comprises the lungs, airways, diaphragm, voice box, throat, nose, and mouth.

Nose: The entrance point for air, with hair acting as a filter for dust, pollen, and allergens.
Nasal Cavity: Lined with mucus and cilia, which filter out bacteria.
Larynx (Voice Box): The passageway for air and the site of sound production.
Pharynx (Throat): The passageway for air and food.

Trachea (Windpipe): Connects the pharynx to the bronchi, allowing air to pass through the neck to the throat.
Bronchi & Bronchial Tree: Pathway for air to travel further into the lungs.
Lungs: The primary site for gas exchange, with two lobes: the left lung is smaller due to the heart's position.
Alveoli: Tiny air sacs within the lungs where gas exchange between the blood and air takes place.

Diaphragm: A dome-shaped muscle that flattens during inhalation and relaxes during exhalation.
Intercostal Muscles: Located between the ribs, help expand the chest cavity during inhalation.
Abdominal Muscles: Assist in exhalation.
Muscles in the neck & collarbone: Also contribute to breathing.

Hemoglobin: The protein in red blood cells responsible for carrying approximately 99% of oxygen throughout the body.

Medulla Oblongata: The part of the brainstem that regulates breathing.
Joint Receptors: Send signals to the medulla during rigorous activity, resulting in increased breathing rate and effort.
Muscles: Respond to signals from the medulla, allowing for efficient oxygen and carbon dioxide exchange.

Congenital Arhinia: Rare condition characterized by the absence of a nose.
Ageing: Lungs can become less efficient with age, leading to decreased lung capacity.
Rhinitis: Inflammation of the mucous membrane lining the nose, often caused by allergens like pollen, dust mites, and animal dander. Frequently characterized by watery eyes and a runny nose.
Sinusitis: Inflammation of the nasal passages or sinuses.
Laryngitis: Inflammation of the larynx, causing hoarseness.
Tonsilitis: Inflammation of the tonsils.
Epiglottitis: Inflammation of the epiglottis, a serious condition requiring tracheotomy to prevent fatal airway obstruction.
Pharyngitis: Inflammation of the pharynx.
Pneumonia: Inflammation of the lungs, often caused by bacterial or viral infections.
Bronchitis: Inflammation of the bronchi, leading to coughing and mucus production.
Asthma: A chronic condition characterized by inflammation and constriction of the airways, causing wheezing and difficulty breathing.
Cystic Fibrosis (CF): A genetic disorder that results in thick mucus build-up in the lungs and other organs, making it difficult to breathe.
Chronic Obstructive Pulmonary Disease (COPD): A group of lung diseases that limit airflow, including emphysema and chronic bronchitis.
Tuberculosis (TB): A highly contagious bacterial infection that primarily affects the lungs.
Emphysema: A condition where air sacs in the lungs are damaged, making it difficult to breathe.

Chest x-ray: Provides an image of the lungs to identify any abnormalities.
Pulmonary function test: Measures lung capacity and function to assess breathing issues.