Hello again, I’m happy that I was able to help you out, even if it was just a little bit. My extended essay is about if there is a link between food and different blood groups. The surprising thing was that when it came to submitting the first draft I had around 700 more words than needed and that’s exactly the great thing about biology that you have so much to analyse. As Ecology is with Biochemistry about my weakest point in Biology I won’t be able to give you tips on that but the tip that I will give you is that you don’t necessarily have to do straight something out of the IB syllabus. For example my title, isn’t really something found in the syllabus. I started off with knowing that I wanted to do something with Biology and as we just finished off the topic with blood, I was really fascinated by it, but then as blood in general is such a broad topic I decided to combine it with food (something else I love), so therefore you could do the same with mesocosm. Have a nice day and let me know if you have any other questions!