I made good progress on testing a number of things related to the mitochondrion piece. I am almost finished piping the edge and then I will confirm that I can successfully attach it to a background. After that I will dye it and work on ways to highlight various portions.
I tried a number of styles of stitching in the background and am happiest with the texture at 12:00. I also learned what not to do in terms of creating some subtle "fingers" of texture. I tried to incorporate some organelles but they got swamped by the background so I now know how to make them stand out. The mitochondrion is 19" x 8"; there was surprisingly little shrinkage. I will be aiming for something about 24" long for the final piece so this scale is definitely proof of concept.
Time = 2 hr, 47 min