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Editor's Notes

1. Hello, I’m Katy Jordan, and today I’m going to give a brief introduction to my Jorum competition entry, which is an online tutorial on the molecular basis of photosynthesis.
2. Why is this important? Photosynthesis is a fundamental process in biology. It’s not really possible to over-state the importance of photosynthesis; it has made life on Earth possible. A deeper understanding of it may also offer potential solutions to reduce atmospheric carbon dioxide, and develop sustainable energy sources.
3. Teaching photosynthesis typically starts from the general principle, defining it as the process by which carbon dioxide is converted to sugar. This definition can be fleshed out and quantified through the chemical equation of the process; that is, six carbon dioxide and 6 water molecules gives one molecule of glucose and six oxygen molecules.
4. An understanding of plant morphology is also important; leaves as the site of photosynthesis, and more specifically within them, the specialised organelles called chloroplasts within them containing the all important molecule, chlorophyll.
5. But, this does not tell the full story. In order to fully understand what is going on, how can we bridge the gap between morphology and chemistry? And by what mechanism does the chemical transformation occur? This is where digital technologies can help.
6. I’m just going to quickly switch from Powerpoint now to the tool. OPEN SAFARI. The online tutorial aims to give an understanding of what is involved in photosynthesis on the molecular level. This can seem very abstract and intangible as it’s not possible to physically observe in this level of detail in real life. In order to address this, the tool combines a narrative panel to the right, which guides the reader through the process, and embedded radio buttons allow readers to ‘see’ what is happening at the point in an embedded 3D molecule viewer to the left, with the most important structural features highlighted. It is important to be able to view the molecules in 3D because the spatial relationship between them facilitates the process. It is also important to have them set within a narrative to guide the learner; when you approach a new topic you don’t know what it is that you don’t know, so if we had Jmol on its own students may not know where to start.
7. To give you a quick example of this: here the reader is guide through the transfer of excited electrons through a photosynthetic reaction centre. The light is first absorbed by a pair of chlorophyll molecules, to another, and then on to pheophytin, causing charge separation and creating potential energy, and then demonstrating how the high-energy electron is trasnferred further, and so on.
8. This format of online tutorial has the potential to be applied to a wide range of teaching scenarios within the biosciences. It was entirely created using Open source and freely available resources; an understanding of writing basic html webpages is required to embed the molecules, but it does not require specialist programming knowledge. Initially I used eXe, which is a tool for creating elearning packages, to create the general structure and navigation system. After this, I manually edited the nest of html pages to embed the 3D molecules using an open-source viewer called Jmol. The files of the 3D molecules themselves which the viewer displays were sourced from the Protein Databank, which is a fantastic online database of 3D crystllographic structures; it currently holds over 67 thousand records and is constantly growing.
9. Thank-you for listening; if you would like to get in touch about anything relating to the tool or how it was made please do drop me an email, my email address is shown here; and I would just like to take a moment to thank the funders and everyone involved in the project that made this work possible, the Teaching for Learning network funded by the Cambridge-MIT institute. Thank you!