Organs of the Respiratory System

The main function of the respiratory system is allowing gas exchange to the different parts of the body. The different organs of the respiratory system include the nose, larynx, trachea, bronchi and lungs. The two types of respiration are aerobic and anaerobic respiration. Aerobic respiration is the kind of respiration which takes place in the presence of oxygen while anaerobic respiration doesn't require oxygen. The human respiratory system organs carry out aerobic respiration and fulfill the oxygen demands of the body. Read more on structure of the human respiratory system.

Organs of the Respiratory System
The different organs of the respiratory system and their functions are described in the following paragraphs.

Nose: It is the organ through which air is inhaled and exhaled. The nostrils / external nares facilitate the process of inhalation and exhalation. Vestibule is a part inside the nostrils which is lined by coarse hair. The cavity of the nose is divided into two parts by the nasal septum. The superior and lateral walls of the nasal cavity are formed of the nasal, maxillary, ethmoid, frontal and sphenoid bones. The floor of the nasal cavity is composed of the hard and soft palates. Cartilage which is the external part of nose, forms its tip and the bridge. The bony shelves which project from the lateral walls of the nose are known as inferior, middle and superior nasal conchae. Meatuses are the spaces present between these conchae. Read more on anatomy of the nose.

Larynx: It is the part of the respiratory system which connects the trachea with the laryngopharynx. The larynx which is formed of cartilages is also known as sound box. Epiglottis, throid and cricoid are the three important cartilages of the larynx. The other cartilages present in the larynx are the corniculate, aryteoid and cuneiform cartilages. The epiglottis, an important part of the larynx is actually a cartilage which prevents the food from entering the respiratory tract. The flap-like action of the epiglottis is facilitated by the corniculate cartilage.

Trachea: The trachea, which lies to the anterior side of the esophagus is a tubular structure with 1 inch diameter and a length of 4.25 inches. Length of the trachea spans between the 6th cervical and 5th thoracic vertebrae. The trachea is composed of around 15 - 20 'C' - shaped pieces of hyaline cartilage. These pieces are held together by the tracheal muscles.

Bronchi: The tracheal tube when divided into two at the caudal end, gives rise to the left and right bronchi. The bronchus is a passage that allows air flow into the lungs. The left bronchus which is shorter than the right one, further divides into 2 lobar bronchi while the right bronchus is divided into 3 lobar bronchi.

Lungs: The lungs are a pair of conical organs present in the pleural cavities. The left lung is divided into 2 lobes (superior and inferior) while the right one is composed of 3 lobes (superior, inferior and middle). Each lung has a median slit and a hilus.

Respiration
In terms of animal physiology, respiration is simply defined as the process in which oxygen from the environment enters the body and the carbon dioxide leaves it. The process of respiration takes place in four stages, i.e. ventilation, pulmonary gas exchange, gas transport and peripheral gas exchange. In the ventilation stage, the air moves in and out of the alveoli present in the lungs. The gas exchange that takes place between pulmonary capillaries and alveoli is termed as pulmonary gas exchange. Gas transport is the process in which the gas moves within pulmonary capillaries, towards the peripheral capillaries present in the organs and then back to the lungs. The process in which the gases are exchanged between the organs / tissues and tissue capillaries is known as peripheral gas exchange. Read more on:

• Aerobic Cellular Respiration
• Aerobic and Anerobic Respiration

The information about organs of the respiratory system and their functions is described in short in the above article. It provides a rough idea about the anatomy and functioning of the respiratory system.