Photosynthesis, the biological process by which light energy is used to convert carbon dioxide and water to sugars, is fundamental to life on Earth and as such a vital component of any undergraduate biology course. Like plant and animal respiration it is a complex process and, despite its central importance, remains an area which students find difficult to comprehend. This difficulty is compounded by the expense and complexity of the equipment available for practical teaching in photosynthesis, making it virtually impossible to provide hands-on teaching to the large class sizes in most undergraduate biology degrees.

This project seeks to provide a new approach to undergraduate teaching of photosynthesis at two levels by the production of a modular interactive multimedia software package containing:

• animated and video materials to explain the basic concepts of photosynthesis, these would serve both as an introduction to the experimental aspects and as stand-alone material for use in undergraduate lectures, and
  
• simulated experimental models of photosynthetic gas exchange and other techniques which can be used either as stand-alone packages or, where equipment is available, to supplement and enrich a laboratory demonstration/experiment. These would provide the students with access to some of the latest techniques in the field, providing an experience and knowledge base which would facilitate understanding of the subject in greater depth.

The first component of this project was designed to replace a first level practical in which students study the effects of light of different wavelengths on photosynthesis in the aquatic plant Egeria. In previous years this practical had yielded extremely unreliable results, often the opposite to that expected. Although results such as these are common to biological systems they are a poor introduction to the complex process of photosynthesis. Obtaining more reliable practical results would have necessitated the purchase of 20 sets of expensive glass filters and provision of a light meter. With practical classes of 80 students (400 total enrollment) this was not practical, but the experiment is a very elegant demonstration of a key concept in photosynthesis. The solution has been the production of a simulation to replace this practical. The prototype was trialed in September 1998. Preliminary feedback from the students has been good and their understanding of the concepts involved has increased dramatically.

This simulation is relatively simple but effective. More sophisticated modules are currently being developed for use in third level plant physiology practical classes.