Uploaded August 2023 | Updated September 2026, 10 hours ago

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You can find all my A Level Biology videos fully indexed at freesciencelessons.co.uk/a-level-revision-videos/a-level-biology

In this video, we look at ATP and hydrogen carriers. First we look at why energy is needed by cells. We then look at the role of ATP as an energy carrier and how this can be formed by substrate level phosphorylation and oxidative phosphorylation. Finally, we explore the role of NAD as a hydrogen carrier.