Inspiration
Lungs are spongy respiratory organs in mammals, birds and reptiles. They are found in the chest cavity and run from the collarbone to the diaphragm. The ribcage surrounds and protects the lungs.
Inspiration is the process by which air is transported to the lungs. In order to get oxygen, the lungs need to work with other body parts and organs within the lymphatic and respiratory systems. The mouth and nose inhale air, which then travels through the mucous membranes and throat. The mucous membranes and the hair-like structures within them called cilia, rid the air of particles such as dust. After this, the air travels through the throat into the trachea, also known as the "windpipe." The trachea is made up of a number of branches of bronchi, through which air passes.
At the same time as the body takes in air through the nose and mouth, the rib cage contracts, making the ribs move upward and outward, and the diaphragm lowers. The chest cavity expands so that it is possible for air to enter the lungs. The air goes through 600 alveoli, balloon-like structures, inside the lungs that expand in order to gather air. The lungs normally take in about one pint of air during one breath, but they can hold 1.3 gallons of air.
Respiration
Respiration is the process by which oxygen is carried from the lungs to different parts of the body. Surrounding the alveoli are blood vessels, which undergo diffusion to send oxygen to tissues throughout the body. Respiration needs to occur for aerobic respiration, which is the process by which the body turns oxygen and nutrients into adenosine triphosphate (ATP). ATP is a molecule that stores energy for bodily processes. Oxygen also needs to reach cells for metabolizing glucose. During respiration, oxygen enters the blood through capillaries, the blood vessels surrounding the alveoli. Carbon dioxide is separated from the oxygen. Oxygen then moves through capillaries into red blood cells before entering the heart. The heart then sends oxygen via blood to other parts of the body.
Expiration
Expiration is the process by which air leaves the lungs and body. During expiration, the body disposes of the carbon dioxide from the air breathed in. During the first part of this process, the muscles around the rib cage relax. The diaphragm and rib cage move back to their original position, and the lungs contract. As a result, the carbon dioxide is forced out of the lungs. Carbon dioxide first has to travel through the capillaries back to the alveoli. After carbon dioxide has entered the lungs, it moves through the bronchi, trachea, larynx, then nose and mouth. As air travels past the vocal cords and larynx, it causes them to vibrate. The vocal cords then send air into the pharynx, producing a sound wave.
Tags: process which, through capillaries, blood vessels, carbon dioxide, chest cavity