Life, what it is not and what may be it is.
20 June 2004 Dov, in Science Forums.
Re what is life :
A) First, what life is not, relating to "statements" in some of the postings:
(1) Isn’t "life an organization of…"? – No. Not more than a car or everything else is an organization of its components.
(2) Isn’t "Evolution of life the increase of biological organization"? – No. It is mostly (not always, f.e. parasites) an increase of complexity. And this not because "raw solar heat (?,DH) is converted into increased complexity"; complexity increases due to ever increasing availability of number of mutatable factors in the organisms.
(3) Isn't it agreed that “influx of heat into an open system will increase the entropy of that system, not decrease it, that all known cases of decreased entropy (or increased organization) in open systems involve a guiding program of some sort and one or more energy conversion mechanisms whereas evolution has neither of these"? – No. Influx in case of life is not just heat translated into motion, and life evolution certainly does have several inherent guiding programs, all plainly scientifically explained.
(4) Isn't it agreed that ”mutations are not organizing but disorganizing mechanisms"? – No. Mutations are neither of these, but inherently occurring unavoidable events in the vast complex systems of evolution.
(5) Isn't it true that “there is still no bona fide proof of evolution, past or present"? – You can't be serious…
B) Next, what life may indeed be :
(1) Life is a system of collecting, using and storing energy. Compare Life with Death.
(2) Earliest life was probably and possibly not yet celled, and consisted of independent individual archaic genes most probably of RNA conformation.
(3) Genes are live organisms that have been undergoing evolution to become dependent members of cooperative communes (chromosomes, genomes) and we are now unable to "roll back their development" for evidence.
(4) Probable early life raw materials on earth's surface were CO2, CO, H2, N2. None or very little free oxygen, thus formation of organic compounds enabled, that evolved into life.
Water was the medium enabling life evolution and celling of primary early archaic RNA genes, as biological lipid bilayer membranes need water to form.
(5) The characteristics of the 4BYA environmental energy, that drove the auto-synthesis of complex living molecular conformations , is not now known.
(6) Ukaryotes arose via ingestion and development of obligate symbiotic relationships which were metabolically specialized. Chloroplasts and mitochondria are compartments within the cells, bound by double membranes. Their DNA is in a circular strand, organized not like in the chromosomes. Comparisons of ribosomal RNA and other molecules have confirmed that they are related to and likely arose from bacteria. Mitochondria were probably free-living bacteria that became cellular endosymbionts and lost much of their autonomy.
By evidence to date mitochondria were acquired only once within eukaryotes. In the case of chloroplasts, evidence suggests that several different types of photosynthetic bacteria contributed to several different episodes of formation of endosymbionts, since there are large differences among chloroplasts and chloroplast DNA.