A respiration organ is an organ that is part of the respiratory system within the body. It works with other respiration organs to facilitate gaseous exchange which is the absorption of oxygen into the body and the expulsion of carbon dioxide. Upper respiratory organs such as the nose, oral cavity and pharynx serve to filter and moisten air as it passes into the body. The lower respiratory system facilitates gaseous exchange with the blood.
There are several respiration organs within the human respiratory system that together, serve to oxygenate the blood. They are responsible for gaseous exchange, where oxygen is transported to the blood, a process known as inspiration. In expiration, carbon dioxide is removed from the blood.
Air passes through the upper respiratory system first, which includes the nasal cavity and nose, pharynx and paranasal cavities. The upper respiratory system is responsible for filtering air as it moves down towards the lower respiratory system. A well known respiration organ, the nose, contains a vestibule with hairs that filter large dust particles from the air. Following on from the nose is the pharynx, which is also part of the digestive system.
Working together in the lower respiratory system are the lungs, bronchi, larynx, also known as the voice box, and trachea. The larynx, which contains the vocal cords, is made of cartilage, and regulates airflow. Moving down from the larynx is a respiration organ called the trachea which is tubular tract that divides into two bronchi; these lead on to the lungs.
Air is forced through these airways, down towards the lungs. Here, the primary bronchi branch into smaller passageways called secondary bronchi, and these divide into even smaller tubes called bronchioles. The lungs are a respiration organ positioned in the pleural cavities. They contain alveoli which perform gaseous exchange with the blood within pulmonary capillaries. The blood is oxygenated and carbon dioxide is removed and sent back up towards the upper respiratory organs.
Respiration organs of different types also exist in other animals. In some small animals, the skin is a respiration organ where air is exchanged through the surface of the body. Fish have gills to breath in water, and some scorpions and spiders use primitive forms of lungs called book lungs. These are made of wrinkly tissue with a large surface area to absorb the maximum amount of oxygen. Some arthropods and invertebrates breath through holes in their body that transport air directly to organs, where it is absorbed.