You can find all my A Level Biology videos fully indexed at https://www.freesciencelessons.co.uk/...

In this video, we look at gas exchange in mammals. First we look at the structure of the lungs, focussing on two adaptations of the trachea. We then explore the structure and function of the alveoli, looking at how the alveoli are adapted for the efficient diffusion of oxygen and carbon dioxide.

This video is aimed at the UK A Level Biology specifications. Students studying International A Level Biology will need to check their specification.

Image Credits:

Tuna
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Stephane-bdc, CC BY-SA 4.0 https://creativecommons.org/licenses/..., via Wikimedia Commons

Salmon
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Hans-Petter Fjeld, CC BY-SA 2.5 https://creativecommons.org/licenses/..., via Wikimedia Commons

Cod
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Hans-Petter Fjeld, CC BY-SA 2.5 https://creativecommons.org/licenses/..., via Wikimedia Commons

Trout
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Public domain

Tiger
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Chrumps, CC BY-SA 4.0 https://creativecommons.org/licenses/..., via Wikimedia Commons

Orangutan
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Bernard DUPONT from FRANCE, CC BY-SA 2.0 https://creativecommons.org/licenses/..., via Wikimedia Commons

Lemur
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Mathias Appel, CC0, via Wikimedia Commons

Polar Bears
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AWeith, CC BY-SA 4.0 https://creativecommons.org/licenses/..., via Wikimedia Commons