One of examiners’ most common criticisms of student answers on ecology, and of those about food webs and energy transfer in particular, is that they are often extremely vague and inaccurate. We shall use the food web below to illustrate this topic. It shows some of the organisms living and feeding in a patch of nettles. There are several advantages in considering this particular food chain. The main one is that these are real organisms and most of them should be familiar to you so they will be easy to remember.