Plant automatic response to climate change (Introduction)

by David Turell , Saturday, December 29, 2018, 15:36 (1950 days ago) @ dhw

dhw: Perhaps I misunderstood your original statement. It’s obvious that complex organisms consist of cells/cell communities performing different functions. But if “cellular function hasn’t really changed since the beginning of life”, do you mean that single cells already had “compartments” for the brain, the liver etc. If not, then clearly cells took on new functions once multicellularity had begun. I’m not making a point here – I’m simply asking for clarification.

DAVID: All the study showed was that single celled bacteria have organelles that have no membrane walls but act as specific organelles doing specific jobs, acting like multicelled organisms in doing compartmentalized work. Your hope for brain in single cells, as you wish above, is found in the layers of the genome control with the onboard information in those layers.

dhw: I didn’t make a wish, though I’m delighted to hear that you now think bacteria may have the equivalent of a brain. I was trying to work out what you meant by “cellular function hasn’t really changed since the beginning of life.” As bacteria do not have brains, livers, kidneys, sex organs etc., all of which require differently functioning cells, I was simply asking for clarification. Do you mean that the organelles are primitive forms of all the different cells that later evolved after the arrival of multicellularity?

Bacteria do everything in one cell, paralleling what multicellular organism do with many organs is all that is imparted. As for brain, don't get exited about bacteria: the bacterial genome contains instructional information to automatically provide necessary responses and to edit its DNA as Shapiro shows, nothing more.