An experiment was conducted to investigate the influence of the variables "realism" and "context" on the performance of biology students on a visual test about the anatomy of a rat. The instruction was primarily visual with additional verbal information like Latin names and practical information about the learning task: dissecting a rat to gain insight into the anatomy of a mammal. Students were tested on: recognition of anatomical objects; labeling of these objects; and relations between objects. Results indicate that the amount of realism and context used in the text influences test performance depending on the learning tasks. Test results also show a learning hierarchy in the different learning tasks with the recognition task being the easiest and the relations task being the most difficult. (Contains 13 references.) (Author/AEF)