As a homage to my scientific background, I chose to explain the concept of Photosynthesis in an assignment called "Maps, Infographic or Edutainment" for my Design in Illustrator class. Photosynthesis itself is a topic that requires several chapters in your university level introductory biology courses to explain and here I've distilled it down to the two most important chemical reactions, The Light Reactions and the Calvin Cycle.
Illustrator afforded me the best tools to create all elements in the piece. I took advantage of the mesh tool and transparent gradients for the pea plant. For the reactions I utilized all the options in the stroke panel to help achieve a perfectly circular pathway.