Surface Tension in Lung Alveoli

Video Summary:
Surface tension is special force between water molecules on the surface. Oxygen and hydrogen atoms in water molecule are partially charged. Positive charge on the hydrogen atom of one water molecule attracts the oxygen atom with negative charge of the other water molecule. Water molecules deep in the water phase experience such attraction in all the directions so there is no net force acting on deep water molecules. However the water molecules on the surface have no other water molecule to pull them outside the water phase. So such water molecules experience net force towards the bulk water phase. As some water molecules are pulled deep in, the remaining water molecules on the surface develop tension. This is surface tension. In lung, alveoli are lined by fluid. And the remaining space in alveoli is filled with air. So there is air-fluid interface in alveoli. This interface tries to decrease it's surface area. And in doing so, they collapse alveoli. So extra pressure is required to expand the alveoli with high surface tension.

🎞More videos on Respiratory Physiology:
● Transport of Gases
● Lung Mechanics

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DISCLAIMER: This video is for education purpose only. Although every effort is made to ensure accuracy of material, viewer should refer to the appropriate regulatory body/authorised websites, guidelines and other suitable sources of information as deemed relevant and applicable. In view of possibility of human error or changes in medical science, any person or organization involved in preparation of this work accepts no responsibility for any errors or omissions or results obtained from use of information in this video.

[hfof]

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[josetrujillo]

This was the nicest explanation: it made it so much easier to get an idea for why surface tension matters in alveoli.

[BeatlesSheeran]

Wow. Watched a lot of Videos about the topic and yours finally explained the concept to me so easily. Thank you so much great teaching!!

[Bee-rwvh]

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[Ragnarson]

this is the best explanation of surface tension i've ever heard
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[tanvirtaswar]

You just blew my mind there with the surface tension how it actually occurs

[marishtadon]

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[sabyasachibhattacharya]

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[mohammadassaf]

the best video explaining surface tension <<<

[atishajaykumar]

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