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Jul 2025
5m 14s

Circulatory System: Alveoli 🫁 GCSE Biol...

Seneca Learning
About this episode

In this episode, we will discuss the alveoli in the circulatory system.

Alveoli are microscopic air sacs within the lungs where the crucial exchange of oxygen and carbon dioxide occurs between air and blood through diffusion.

Their structure is highly adapted for this vital process, featuring a vast surface area and an extensive network of surrounding capillaries that ensure a rich blood supply and minimal diffusion distance.

Deoxygenated blood flows to the alveoli, where it releases carbon dioxide and absorbs oxygen before returning to the body as oxygenated blood.

Notably, in some marine mammals like whales, alveoli function differently during deep dives, temporarily shutting down as these animals rely on stored oxygen.

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