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You are watching: Your respiratory system transfers oxygen to your . Cologne, Germany: Institute because that Quality and Efficiency in Health treatment (IQWiG); 2006-.


Our lungs are among our largest vital organs. The oxygen you breathe in goes into your lungs and also passes into your blood from there. That is climate transported to every the cell in her body with your bloodstream. The lung are situated in the chest region, protected by the ribs in the rib cage. Their structure can be contrasted to that of an upside-down tree: The windpipe branches right into two airways called bronchi, which bring about the lungs. Inside the lungs, the airways store branching into narrower airways till the wait sacs room reached.

What is pulmonary circulation?

When you breath in (inhale), waiting containing oxygen enters her windpipe, passes through the bronchi and also eventually get the air sacs. This air sacs, called alveoli, are responsible for gas exchange. Lock look a little bit like grapes at the finish of the bronchial branches. Healthy and balanced lungs have about 300 million air sacs in them. Each air sac is surrounded by a network of fine blood ship (capillaries).

The oxygen in inhaled air passes throughout the thin lining of the wait sacs and also into the blood vessels. This is known as diffusion. The oxygen in the blood is then carried roughly the body in the bloodstream, getting to every cell. Once oxygen passes right into the bloodstream, carbon dioxide leaves it. Carbon dioxide (CO2) is a rubbish product of cellular metabolism. You eliminate it when you breathe out (exhale). This gas is transported in the opposite direction to oxygen: It overcome from the bloodstream – throughout the lining that the air bag – right into the lungs and also out right into the open.


What happens when you breathe?

When you breath in, your chest and lungs expand. As soon as you breathe out, her lungs gain smaller again. Both of these activities are caused by the diaphragm and muscles that run between the ribs (intercostal muscles). Us breathe without having to think around it.

When in ~ rest, adults breathe 14 come 16 times every minute. About half a liter of wait is inhaled during one common breath. When you are an ext active, her breathing becomes faster and deeper in order come get much more oxygen right into your blood.

A person’s basic fitness significantly depends on exactly how well their lungs and heart work. Her lung role can be measured using various breathing tests.

The structure of the lungs

In adults, the windpipe (trachea) is about ten centimeters long and also branches into two key bronchi well-known as the ideal bronchus and the left bronchus. These key bronchi then divide into smaller secondary bronchi (lobar bronchi) – three in the ideal lung and also two in the left lung. Over there is much less room in the left lung since it shares an are with the heart.

The an additional bronchi climate branch into a variety of tertiary bronchi (segmental bronchi). The appropriate lung is consisted of of ten locations known as bronchopulmonary segments. The left lung is made up of ripe of this segments. Every segment is supplied by its own tertiary bronchus and its own branch that the pulmonary (lung) artery. This means that individual segments have the right to be gotten rid of if necessary, for instance because of a significant lung an illness or injury.

The windpipe and bronchi room lined through mucus-producing cells and millions of small hair-like projections referred to as cilia. If you breath in harmful substances like dust or various other particles, the mucus and cilia ensure the they don’t continue to be in your lungs: international matter gets caught in the mucus, and also the cilia constantly move back and forth, transferring the mucus the end of her lungs into your throat, where you one of two people swallow the or cough it out. If larger foreign objects get in the windpipe, a sneeze reflex is triggered.

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Menche N. (Hg.) Biologie Anatomie Physiologie. München: urban & Fischer/ Elsevier; 2012.