o For every cell of the body to function there is a need of supply of constant oxygen. This constant supply and availability of oxygen and exchange of gases are conducted the respiratory system of the body.
o From the nasal cavity to lungs, from different centers to the receptors regulating the respiration all are part of the human respiratory system.
o There are different portions for different responsibility. Conducting portion that includes the nose, nasal cavity, trachea, bronchi and bronchioles that help in transporting the air through the system and there is respiratory system that helps with gas exchange and includes the bronchioles with the alveoli and alveolar ducts.
Parts of Human Respiratory System
It is divided into two parts – upper respiratory tract (nose to larynx) and the lower respiratory tract (trachea to below).
I. Upper Respiratory Tract
o Upper respiratory tract helps with the passing the air, filtering and humidifying it through and help of parts i.e., nose and nasal cavity, paranasal sinuses, pharynx and larynx.
o Sinuses are the small openings present in bones of head, hollow spaces in the bones connected to the nasal cavity. It helps in the regulation of humidity and temperature of the air taken in.
o Nose and nasal cavity are the first part of the system helping the filtration of the air inhaled. Air is also inhaled in through the mouth oral cavity and passed through trachea to the lungs.
o Pharynx is the throat that helps in passing the air downward to the lungs through trachea.
o Larynx is said to be the voice box of the system. The movement of air that we breathe in and out creates the voice sounds.
Human Respiratory System Diagram
II. Lower Respiratory
o Lower respiratory includes trachea that is known as windpipe that extends to lungs as bronchi.
o Bronchial tree is the branched part of the system making an air conducting passage. These bronchial trees extend from the bronchi to form the terminal bronchioles.
o Alveoli are the air sacs found at the end of terminal bronchioles present with their alveolar ducts.
o Lungs is the most important part of the system, sac like organ responsible for the inspiration and expiration of the gases with the exchange of gases. The right lungs have three lobes whereas, right lungs have two lobes. Lungs have pleura which is the two membranes that surrounds the lobes and separates lungs from the chest walls.
Muscles in the Respiration Process
o Intercoastal muscles helps in elevate the ribs by the contraction of external intercostals. This increases the dimensions of the thoracic cavity.
o Diaphragm is the muscles that separates chest cavity from abdominal cavity and helps in the expansion of lungs for inhaling the air.
o There is no need of muscular effort for normal exhalation.
Blood Supply of Lungs
o Pulmonary and bronchial circulation (that takes the oxygenated blood to the tissues of the body and carry away the deoxygenated blood from tissue and exchanged in the alveoli.
Regulation of Human Respiration
o Respiratory centers including the medulla and pons controlling the rate of breathing in the lungs and signaling when abnormal cases are observed.
o Chemo and sensory receptors present throughout the system signals the centers about the working of the parts of the system and regulating the pH of the system.
Functions of Respiratory System
o Filtration of the inhaled air so that it no foreign particles enter the system.
o Respiratory system is responsible for the production of voice with the help of larynx (voice box)
o The blood pH is also regulated by the respiratory system with the help of chemo and sensory receptors.
o The main function is to exchange of gas of the inhaled air and provide oxygenated blood to the tissue and remove the carbon dioxide out of the body by the help of air sacs alveoli present in the lungs.
o Also contains receptors that help in smell.
Respiratory System Disorders
o Even there are some disorders observed when certain function or the part of respiratory system is not working as required.
o Asthma – observed when the mucus production increases and the airways are narrow.
o Bronchiectasis – infection that causes inflammation in bronchial walls and makes it thicker.
o Chronic obstructive pulmonary disease – this is a type of long-term condition if not treated well then it might get worse.
o Pneumonia – a type of infection that causes inflammation in the alveoli and filled with pus.
o Tuberculosis – one of the major disorders observed in the respiratory system. Mycobacterium tuberculosis causes this disorder and multiplies to spread the effect. It may also target other organs like kidney, brain and spine.
o Lung cancer – tumor in the lungs due to the abnormal growth of the cells of lungs. This may be due to smoking other underlying reasons. May lead to chronic situation if not treated early.
o Cystic fibrosis – this is an inherited genetic disorder observed in the lungs. This causes in production of mucus in the system and causing infection in the lungs.
Respiratory System Disorder Treatments
Most of the disorders can be prevented by certain lifestyle changes.
o Avoid smoking: Smoking is one of the harmful ways to deteriorate the respiratory system and causing the disorders and diseases.
o Avoid the places that can be passive smoke area – even a secondhand smoke can lead to the deterioration of the system.
o Being physically healthy and keeping weight in check so that this helps in keeping the lungs healthy and well-functioning. As the weight increases the respiration ability weakens.
o Limit the air pollution exposure. Harmful gases contribute to many respiratory system disorders.
o If any allergy is observed due to any gas, materials or fumes use of protective gears should be encouraged to avoid unnecessary discomfort.
You may like to read;
Human Respiratory System Citations
- Lung hysteresis: a morphological view. Histol Histopathol . 2004 Jan;19(1):159-66.
- Anatomy and bronchoscopy of the porcine lung. A model for translational respiratory medicine. Am J Respir Cell Mol Biol . 2014 Sep;51(3):334-43.