What's the Point of Plants?

Brian Cox and Robin Ince are joined on stage by plant biologist Professor Jane Langdale, physicist Professor Jim Al-Khalili and comedian and former horticulture student Ed Byrne to ask, "what's the point of plants?". How would the evolution of life on our planet have differed without plants, and what would our planet look like today? Most crucially that seemingly dull but necessary process of photosynthesis that we all learned about in school, is in fact one of the most important processes in our universe, and as usual it seems, the physicists are trying to take credit for it. Could there be a quantum explanation for how this amazing reaction works, and if so, are plants in fact the perfect quantum computers?