There is an interview with Gromov: http://www.ihes.fr/~gromov/PDF/rtx100300391p.pdf

Q: (...) an you describe your involvement and how your mathematical and geometric insights can be useful for problems in biology?

Gromov: I can explain how I got involved in that. Back in Russia, everybody was excited by ideas of René Thom on applying mathematics to biology. My later motivation started from a mathematical angle, from hyperbolic groups. I realized that hyperbolic Markov partitions were vaguely similar to what happens in the process of cell division. So I looked in the literature and spoke to people, and I learned that there were so-called Lindenmayer systems. (...)

And his paper on the subject: "Cell Division and Hyperbolic Geometry" http://www.ihes.fr/~gromov/PDF/16%5B71%5D.pdf

There is an interview with Gromov: http://www.ihes.fr/~gromov/PDF/rtx100300391p.pdf

Q: (...) an you describe your involvement and how your mathematical and geometric insights can be useful for problems in biology?

Gromov: I can explain how I got involved in that. Back in Russia, everybody was excited by ideas of René Thom on applying mathematics to biology. My later motivation started from a mathematical angle, from hyperbolic groups. I realized that hyperbolic Markov partitions were vaguely similar to what happens in the process of cell division. So I looked in the literature and spoke to people, and I learned that there were so-called Lindenmayer systems. (...)

And his paper on the subject: "Cell Division and Hyperbolic Geometry" http://www.ihes.fr/~gromov/PDF/16%5B71%5D.pdf

I was just reading: Visions in Mathematics: GAFA 2000 Special Volume, Part I. Gromov's article in the collection, titled: "Spaces and Questions" has a subsection: "Symbolization and Randomization" which you might find interesting, he discusses "random manifolds" at length and even touches on one of the questions in his talk: assembling combinatorial manifolds out of simplices (i.e. how many triangles).