In this project, I spent a lot of time drawing parts of the human skeleton and muscle groups. It's more than that though. This is completely done with a fine tip pen and dots to make up the image. Also known as stippling, or pointillism. I plan on drawing all parts of the body this way soon.
For the muscle part, the drawing is done on clear acetate paper. It's more challenging because of the chances of smearing your work. If someone wants to show the piece on an overhead projector, if you know what that is, then the person may do so to show the work with all of the details.