Uploaded October 2023 | Updated September 2026, 1 day 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 start the photosynthesis topic. First we look at what is meant by autotrophic and heterotrophic organisms. We then look at the two key reactions in photosynthesis, which are called the light-dependent reactions and the light-independent reactions. We explore how these reactions link together.