What is Gas exchange?
[[File:Gas exchange in the aveolus simple (en).svg|200px|right|Gas exchange in humans. Oxygen and carbon dioxide switch places between a [[capillary]] (part of the bloodstream) and an [[alveolus]] (an air sac in the lungs).]] '''Exchange of gases''' or '''gas exchange''' is carried out by [[organisms]]. [[Animals]] breathe out [[carbon dioxide]] and breathe in [[oxygen]]. [[Plants]] use carbon dioxide to carry out [[photosynthesis]], which makes oxygen. Plants only do this out during the day, when there is sunlight. Plants [[respiration|respire]] all day and night. In the human [[respiratory system]], gas exchange happens in the [[alveolus]] ([[alveoli]] for plural). These are in the [[lungs]] and help with diffusion. [[Oxygen]] [[diffusion|diffuses]] into the bloodstream, from the air. Oxygen is used in [[aerobic respiration]]. [[Carbon dioxide]] diffuses out of the bloodstream, into the air. Carbon dioxide is a waste product made by [[respiration]].<ref> Kety S.S. 1951. The theory and applications of the exchange of inert gas at the lungs and tissues. ''Pharmacological Reviews'' '''3''' (1): 1–41. [https://pubmed.ncbi.nlm.nih.gov/14833874/]</ref> == References == {{reflist}} {{biology-stub}} [[Category:Physiology]]