human respiratory system

Nasal Cavity

Main entrance for airflow; filters and humidifies air to prevent foreign particles from entering the lungs.

Pharynx

Tube-like passage where food and air tubes meet; contains the epiglottis at its lower end.

Larynx

Airway with vocal cords attached; located below the pharynx.

Trachea

Air passage under the larynx that runs down behind the breastbone.

Bronchi

Found at the base of the trachea; branches into left and right bronchi to deliver air to the lungs.

Bronchioles

Delivers air from bronchi to alveoli.

Alveoli

Tiny branches at the end of bronchioles where gas exchange occurs.

Lungs

Main organs located in the thoracic cavity filled with air spaces.

Respiration

Overall exchange of gases between the atmosphere, blood, and cells.

Breathing

Process of air moving in and out of the lungs.

External Respiration

Exchange of oxygen and carbon dioxide between the air and blood in the lungs.

Internal Respiration

Exchange of gases between the blood and body cells.

Gills

External and internal structures for gas exchange in aquatic animals.

Lungs

Organs for gas exchange in land animals.

Tracheal Systems

Used by insects for gas exchange.

Inhalation

Process where diaphragm contracts, air comes in, and pressure in the lungs decreases.

Exhalation

Process where diaphragm relaxes, air goes out, and pressure in the lungs increases.

Common cold

Viral infection with symptoms like sneezing, runny nose, and mild fever.

Influenza

Contagious illness caused by mycoviruses, leading to pneumonia; vaccines and antiviral drugs can help.

Pneumonia

Lung infection with symptoms like fever, chest pain, and fluid in the lungs.

Tuberculosis

Contagious disease caused by mycobacterium tuberculosis with symptoms like persistent cough and weight loss.

Bronchitis

Inflammation or swelling of the bronchial tubes, can be acute or chronic.

Asthma

Chronic allergic reaction causing narrowed and swollen airways with increased mucus production.

Emphysema

Lung condition causing shortness of breath and reduced oxygen in the blood due to respiratory irritants.

COPD

Chronic lung disease leading to breathing difficulties, cough, mucus, and wheezing.

Lung cancer

Cancer caused by bacteria, spreading through respiratory droplets; symptoms include cough, weight loss, and pain when breathing.