Depending on what a gel interacts with, it will have different behaviors. A gel is a polymer, a long chain of monomers, or molecules, that are cross-linked like a web of fibers. It is those links, which allow a gel to capture water within them, that give gels their elasticity and fluidity. The fundamental principles that govern the swelling equilibrium and dynamics also turned out to be a powerful paradigm for understanding the molecular basis of polymer behaviors in general. Professor Tanaka was exploring the idea that gels may provide a clue to the baffling puzzle of how life on Earth began.
Life boils down to amino acids.
They line up in chains called polymers. Scientists can determine the sequence of amino acids that make up specific proteins, but they don't know how to make one from scratch. Professor Tanaka's laboratory is working on synthesizing a gel with characteristics similar to those of proteins capable of recognizing a target molecule. The current theory holds that back in the Earth's early days, amino acids swimming around in a primordial soup randomly came together in a viable sequence. This theory didn't hold much water with Professor Tanaka.