respiratory system

The respiratory system is responsible for breathing (pulmonary ventilation) and respiration (gas exchange).

The mechanical process of getting air into and out of the lungs. It involves the intake of oxygen during inspiration and the release of carbon dioxide during expiration.

The chemical process of taking in oxygen and releasing carbon dioxide. Takes place at the cellular level to produce energy. It includes glycolysis, pyruvate oxidation, the Krebs cycle, and oxidative phosphorylation.

Nose, Nostril, Epiglottis, Pharynx, Larynx

Filters, warms, and humidifies incoming air. It also protects the delicate lower respiratory tract and reabsorbs heat and water in outgoing air.

The passageway for air from the atmosphere into the respiratory tract. It contains cilia (microscopic hair-like structures) that filter out particles like dust.

A flap of tissue that is up during breathing to allow air into the larynx. It folds back over the glottis during swallowing to prevent food from entering the airway.

Connects the mouth and nasal cavity to the esophagus. It filters, warms, and humidifies air. The pharynx is divided into three sections: nasopharynx, oropharynx, and laryngopharynx.

Produces sound (voice box). It protects the trachea against food aspiration and contains cartilage (epiglottis, thyroid, cricoid) that surrounds and protects the glottis.

Conducts air to and from the gas exchange surfaces

Connects the larynx and pharynx to the lungs. It filters inhaled air and directs it to the bronchi. The trachea is a tough, flexible tube.

Trachea, Bronchi, Bronchioles, Lungs, Alveoli, Diaphragm

Two air passageways branching out from the trachea, directing air into the lungs. They branch into smaller tubes called bronchioles. The right bronchus is wider and at a steeper angle than the left.

The main organs of respiration. This is where oxygen is taken in and carbon dioxide is expelled.

Smaller tubes connected to the bronchi, located within the lungs. They have thick smooth muscle that can constrict (decrease airflow) or dilate (increase airflow).

Tiny, sac-like structures at the ends of the bronchioles. They are the site of gas exchange between the air and the blood. Alveoli are surrounded by a network of capillaries for efficient gas exchange.

A dome-shaped muscle at the bottom of the lungs. It contracts and relaxes to force air in and out of the respiratory tract.

Noninvasive tests that assess how well the lungs are working.

Vital Capacity, Expiratory Reserve Volume, Tidal Volume

Amount of air exchanged during normal breathing. 500ml - male 400ml - female

Amount of extra air exhaled forcefully after normal exhalation 1100:male 800:female

Total amount of air exhaled after maximum inhalation. 4600:male 3400:female

Air Pathway: Nostrils → Nasal Cavity → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli.