single cell to multicell (Introduction)

by David Turell , Friday, December 05, 2014, 01:45 (3641 days ago)

Highly complex process, not yet understood:-http://phys.org/news/2014-12-eukaryotic-cell-endosymbiont.html-
"One good example of how to quickly get confused when favoring a gene-centric approach at the expense of paleontologic or structural organelle-level analysis is with ribosomes. While horizontal, lateral and verticle gene flow among bacteria, archaea, and eukaryotes are constant confusers across species, the ribosomal RNA and riboproteins that exist in several unique cell-trafficking or inheritance scenarious in the organelles of single cell can be even more confounding. Cavalier-Smith has offered several ideas here to explain the size changes that have occured in the evolution of particular ribosomal subunits found in mitochondrial and nuclear DNA, as well as the localization motifs they have. -"In a follow up post we will address some of the main structural features of cells that have been critical in defining the evolutionary path taken by eukaryotes. Chief among these are the different ways that various kingdoms of life make their membranes, cytoskeletons, and cilia. We will also explore the precursors to spliced introns, centrioles, meisosis, recombination, sex, and perhaps multicelluarity. The finer scale structure of golgi, and the bacterial precident for mitochondrial cristae should also be included. Finally we will look at some attempts to root major eukaryotic developments in terms of the ecological background of Earth, its oxygenation, and maybe even a glaciation event or two."