Respiratory Anatomy
*Provided by the American Lung Association
Sinuses* (frontal, maxillary and sphenoidal)
Hollow spaces in the bones of the head that are connected to the nose by small openings, the sinuses are responsible for monitoring the temperature and humidity of the air breathed in, as well as adding resonance to the voice.
Nose* (nasal cavity)
Optimal entrance for inhalation due to hairs lining the walls and filtering the air.
Cilia*
Very small hairs that have a wave-like motion that is responsible for carrying mucus into the throat where it is coughed up or swallowed.
Mucus*
Sticky phlegm, liquid. Mucus traps dust, germs and unwanted matte that has invaded the lungs. It is disposed of by coughing, sneezing, clearing your throat and swallowing. Tall cells lining the bronchioles secrete this mucus which traps dirt and travels to the mouth and nose by use of the cilia.
Mouth (oral cavity)*
Secondary entrance for inhalation.
Adenoids
Lymph tissue located at the top of the throat, these can be removed for medical reasons such as enlargement that interferes with breathing. The lymph system is made of nodes (knots of cells) and vessels that are responsible for carrying fluid around the body. It is also a part of the immune system and is necessary for producing lymphocytes to fight infection and germs, and for filtering foreign matter out of the body to resist infection.
Tonsils*
Responsible for fighting germs, but these lymph nodes in the wall of the throat often become infected and in many cases are removed.
Pleura
A continuous membrane folded over itself, the pleura is often considered two. This surrounds each lobe of the lungs, separating the lungs from the chest wall.
Diaphragm
Part of the muscular system and a major part of respiration; this strong wall of muscle is situated between the chest cavity and the abdominal cavity. Moving downward creates suction in the chest and draws are in while expanding the lungs. Exhalation is the opposite process.
Ribs
Slightly moving part of the skeletal system that is responsible for the protection of the chest cavity.
Intercostals
Muscles between the ribs
Lymph Nodes (in the lungs)
Located against the walls of the bronchial tubes and trachea, they are a part of the immunity response.
Throat (pharynx)*
Acts as a passageway allowing air coming in from the nose and mouth into the trachea (windpipe).
Epiglottis*
This simple flap of tissue protects the entrance of the trachea, opening during respiratory functions and closed while swallowing to re-direct substances other than air to the esophagus and stomach.
Voice Box (larynx)*
As holder of the vocal chords, this is the site where the movement of air caused by inhalation and exhalation provides the sound of our voice.
Esophagus
Passageway from the mouth and throat to the stomach.
Windpipe (trachea)*
Passageway from the pharynx to the lungs.
Bronchial Tubes*
The trachea divides into two main tubes, known as the Bronchial Tubes, one going towards each lung. These then divide into a branch for each lobe of the lungs which then divide further.
Right Lung
The right lung is made of three lobes, sections. Each lobe is filled with alveoli, air sacks, and the air moves in and out through one bronchial tube.
Left Lung
The left lung is made of two lobes, sections. Each lobe is identical to those of the Right Lung.
Bronchioles*
The smallest subdivisions of the bronchial tubes and the location of the air sacs (singular alveoli, plural alveolus)
Alveoli
These air sacs are the final destination of the air taken in during inhalation before entering the circulatory system.
Capillaries
Blood vessels and members of the circulatory system, they are imbedded in the walls of the alveoli where oxygen diffuses into the blood they contain and carbon dioxide (a waste product) replaces it in the alveoli to be exhaled.
Pulmonary Artery
Blood that is oxygen-poor is carried to the capillaries around the alveoli.
Pulmonary Vein
Oxygen-rich blood returns to the heart and blood stream via the pulmonary vein.
*These anatomical sites are members of the respiratory system's Conduction Zone and do not administer to the processes of gas exchange, anatomic sites in which gas exchange occurs are part of the Respiratory Zone.