Its quite visceral. Does he have any background in medical illustration?
He could probably have a lot of fun with a generative art tool like Structure Synth ( http://structuresynth.sourceforge.net/ )
Structure synth will make germ-like looking pictures out of the box with no modification. It even comes with many presets. However its not so predictable what it generates. I have never really been so excited about it. However it is easy to use. Another similar program is Mandelbulb. Which makes 3D fractals and renders them.
A bit more is involved in learning and setting up the sverchok add-on for the 3D program Blender but it is much better for an artist, I think, in terms of predictability/controllability.
Sverchok is a tool to let Blender artists design shapes with various kinds of math-based morphology, similar to the way plants, microbes, etc. grow - based on manipulation of mathematical functions. It was originally meant for architects to design buildings.
But one doesn't need to know a lot of math to have a lot of fun with sverchok.
A little bit of basic math is good.
http://nikitron.cc.ua/sverchok_en.html
https://github.com/nortikin/sverchok
And of course there are programs like Apothesis for Windows which do amazing fractal flame imagery.
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