Biological complexity: phase separation (Introduction)

by dhw, Monday, November 07, 2022, 12:41 (747 days ago) @ David Turell

QUOTE: How do the right proteins organize themselves in a sea of fluid swarming with millions of molecules? Do they bump into each other by chance, or does the cell actively organize its fluid space to bring the correct partners together?

Thank you for this. It’s almost impossible for us large organisms to get our heads round the fact that this unit of life – so tiny that we can’t even see it with the naked eye - is itself an immensely complex community of interactive parts. There is no way the organization can be left to chance, and the author offers only one alternative: cells actively organizing themselves. And if they do this individually, they will also do it collectively in the cell communities that cooperate to form organs and organisms, as well as to make the changes that respond to new circumstances and result in new species. Human societies self-organize in the same way, and we would laugh at the idea that they run automatically (see “quorum sensing” below). Our communities are organized by their own intelligence, no matter what may have been the original source of that intelligence. And so if cells self-organize as we do, and their communities self-organize as our communities do, is it not logical to argue that their self-organization is run by their intelligence, just as ours is?

Quorum sensing: how it works in bacteria and viruses

DAVID: obviously both bacteria and viruses have receptors for these specific signaling molecules and built-in automatic responses to the levels involved.

As usual you shove in the word “automatic” but the process described above is the equivalent of describing all the physical processes by which we humans communicate and act once we have taken a mental decision on what to do. Yes, if I decide to talk to you, I will activate all kinds of chemicals and tissues and muscles and electrical impulses. But they are all the consequences of what is NOT automatic: namely the decision to talk to you. Bacteria and viruses must decide on the best course of action before they set in motion the physical processes that will implement their decisions.