Respiratory system

The respiratory system consists of the lungs and airways, which extend from the mouth and nasal cavities into the chest. The airway runs parallel with the upper digestive tract, and the lungs sit within the chest cavity, above the heart and behind the ribcage. The system also includes various accessory muscles that allow air to enter and leave the airways by altering pressure within the chest cavity.

The system is responsible for gas exchange, bringing oxygen into the lungs and releasing carbon dioxide into the air in the process we know as breathing. Various environmental and genetic factors can hinder the gas exchange process, by blocking the airways or destroying the lung tissue. Common disorders are bronchitis, asthma, chronic obstructive pulmonary disease (COPD), and lung cancer.

Image by Theresa Knott

Parts of the Respiratory System

Nose: Air can be pulled in through the nostrils into the cavity above the throat (nasopharynx)

Mouth: Air can be pulled in through the mouth and into the throat (oropharynx)

Larynx: The voicebox, a cartilage ring with skin folds that vibrates as air passes through it, produces sounds and vocalizations

Trachea: The muscle and cartilage structure in the throat knwon as the windpipe

Bronchi: The bronchi are two branches (left and right) off the windpipe into each lung

Bronchioles: Smaller and smaller branches off the main bronchi making up the bronchial tree within the lungs

Lungs: The main organ for gas exchange. It is made up of air sacs called alveoli.

Respiratory muscles: diaphragm, intercostals