MYSTERY OF LIFE.

Otago Daily Times, Issue 19904, 25 September 1926, Page 9

MYSTERY OF LIFE.

POWER OF SELF-REFORMA-TION. PHYSIOLOGICAL CHEMISTRY. Professor J. B. LeatheSi president of the Physiology Section of the British Association, had a keen audience for an address of unusual lucidity and interest. “Ultimate analysis of the phenomena with which physiology deals,” he said, “leads to the fundamental distinction between matter m which life is manifested and matter in which it is not. Life is exhibited only in aqueous systems, containing unstable, perishable combinations of carbon with hydrogen, nitrogen, sulphur, phosphorus, and oxygen, in the presence of certain inorganic irons, those which are present in the sea, the native environment originally of all forms of life; and the inalienable property that such matter exhibits when alive, and that matter which is not alive does not, is that these unstable organic combinations are for ever reforming themselves out of simpler combinations that do not exhibit this property, and do so at a rate which averages at least hot less than that at which they break down. This

power of self-reformation, spontaneous regeneration. operates not only when living organisms, cells, or communities oi cells are growing or reproducing their kind; the very maintenance of living existence requiries by definition that it should persist. In the absence of water the living process may sometimes apparently be suspended for a time, as it may be if the surrounding watery medium is immobilised by cold; it is a question whether this is anything more than retardation to a rate of change that is imperceptible by the ordinary methods of observation, and a. question bow | Oll such suspended animation is possible where it is possible at all. It is only where water has the kinetic activity of the liquid state that spontaneous regeneration of living matter can in general proceed, and then it must, for when it ceases the unstable mater-

iai ceases to live.” Nest ho contrasted customary comparisons of the growth of crystals with the growth of living matter, and showed that the two phenomena wore inconceivably ditferent. The peculiar thing about the chemistry of living matter was not that its characteristic reactions were novel, but that in tho rough and tumble of ordinary aqueous systems their occurrence was almost infinitely improbable. And yet where there was life circumstances existed which made them the rule. The body of ms address was a detailed exposition of the chemical peculiarities of life and of our present remoteness from any adequate explanation of them. But ho ended on a hopeful note. A STREAM WITH MANY SOURCES. “Physiological inquiry," ho said, “is a stream that has many sources; its waters gather from quarters far removed from one another. A marvellous meeting took pltmc in the early years of this century when the forgotten experiments of Mendel came to the surface again, and found corroboration in the cytological studies that from about the same time had pursued their slow obstructed way above ground in the en deavour to elucidate the changes in tho

nucleus of maturing germ cells. “In a resting germ cell the chromosomes form an even number, characteristic of tho species; they consist of half that number of pairs of homologues, one of each pair descended from the paternal element in tho last zygosis, the other from the maternal. At one of the cell divisions by which the germ cell gives rise to the mature gamete, with half the characteristic number of chromosomes, thcro occurs a segregation of tho two members of each pair so that they pass into different gametes; the exact cytological equivalent of Mendetian segregation of allelomorphic pairs of characters. To-day the study of genetics and of the ‘topographical anatomy; of the chromosomes, with ns groupings’ and ‘crossings over, seems to call out for chemical assistance. . “It may bo that in the lifetime of some of us these confluent streams_ of thought and experiment aro to be joined by yet another that rises in tho vast, remote, and, as it must appear to some, muddy, swamp, of physiological chemistry; and it then, forgetting its ‘foiled, circuitous wander ingf,’ wfll form with them a majestic river, brimming and bright and largo.