If you're an Edexcel Biology AS student, you're probably studying from the Pearson 'Edexcel AS biology students' book'. Topic 3 and 4 got a lot of unnecessary topics in it, I'm sure many can agree. I, unfortunately, can't differentiate between what's unnecessary and what's actually there in our specification. I was hoping you could help me with that. Just please tell me which pages are there in our specification and which ones I should pay no attention to.