Life, Its Nature, Origin and Maintenance: An Address Delivered to the British Association for the Advancement of Science, at Its Meeting at Dundee, in September, 1912Longmans, Green and Company, 1912 - 36 страница |
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abiogenesis action activity aggregate amoeboid appearance arteries associated assumed became blood blood-vessels body Brit cell-aggregate changes chemical agents chemist chemistry co-ordination colloid complex contraction course of evolution Dastre death definite disassimilation disease Duodenum effects emotions essential evolution of living evolutionary evolved existence favourable fertilisation fluid formation functions gastric juice globe growth heart Herbert Spencer higher animals hormones impressions inanimate individual cells influence inorganic internally secreting gland involuntary muscle juice living and non-living living matter living organisms living substance maintenance mammary gland manifestations Meldola Metazoa meteorite micro-organisms microscope movements nerve-cells nerve-fibres nervous system non-living matter nuclear matter nucleus nutrient nutrition occur organic chemistry origin ovum oxygen pancreas parathyroid phenomena phenomenon Physiologie pituitary possessing possibility Presidential Address produced prolonged Protista protoplasm recognised regarding Regulation reproductive result scientific senescence sexual reproduction similar solution spontaneous stimulate suprarenal capsule surface tension take the form term thyroid tion tissues vital white corpuscles
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Страница 35 - The days of the years of my pilgrimage are an hundred and thirty years : few and evil have the days of the years of my life been...
Страница 14 - But though I cannot express this conviction of mine too strongly, I must carefully guard myself against the supposition that I intend to suggest that no such thing as Abiogenesis ever has taken place in the past, or ever will take place in the future.
Страница 16 - Knowing what we know, and believing what we believe, as to the part played by evolution in the development of terrestrial matter, we are, I think (without denying the possibility of the existence of life in other parts of the universe 17) justified in regarding these cosmic theories as inherently improbable...
Страница 17 - ... upon it from the study of the evolution of matter in general, we are led to regard it as having been produced, not by a sudden alteration, whether exerted by natural or supernatural agency, but by a gradual process of change from material which was lifeless, through material on the borderland between inanimate and animate, to material which has all the characteristics to which we attach the term "life.
Страница 18 - Spontaneous generation of life could only be perceptually demonstrated by filling In the long terms of a series between the complex forms of Inorganic and the simplest forms of organic substance. Were this done, it is quite possible that we should be unable to say (especially considering the vagueness of our definitions of life) where life began or ended."— K.
Страница 18 - It is true that up to (he present there is no evidence of such happening ; no process of transition has hitherto been observed. But, on the other hand, is it not equally true that the kind of evidence which would be of any real value in determining this question has not hitherto been looked for? We may be certain that if life is being produced from non-living substance, it will be life of a far simpler character than any that has yet been observed — in material which we shall be uncertain whether...
Страница 14 - Nor should we expect the spontaneous generation of living substance of any kind to occur in a fluid the organic constituents of which have been so altered by heat that they can retain no sort of chemical resemblance to the organic constituents of living matter. If the formation of life — of living substance — is possible at the present day — and for my own part I see no reason to doubt it — a boiled infusion of organic matter — and still less of inorganic matter — is the last place in...
Страница 10 - Living substance or protoplasm always, in fact, takes the form of a colloidal solution. In this solution the colloids are associated with crystalloids (electrolytes), which are either free in the solution or attached to the molecules of the colloids. Surrounding and enclosing the living substance thus constituted of both colloid and crystalloid material is a film, probably also formed of colloid, but which may have a lipoid substratum associated with it (Overton). This film serves the purpose of...
Страница 11 - ... living body into the materials which are given out from it. But since the initial processes and the final results are the same as they would be on the assumption that the changes are brought about in conformity with the known laws of chemistry and physics, we may fairly conclude that all changes in living substance are brought about by ordinary chemical and physical forces.
Страница 11 - Even so complex a process as the division of a cell-nucleus by karyokinesis as a preliminary to the multiplication of the cell by division — a phenomenon which would prima facie have seemed and has been commonly regarded as a distinctive manifestation of the life of the cell — can be imitated with solutions of a simple inorganic salt, such as chloride of sodium, containing a suspension of carbon particles ; which arrange and rearrange themselves under the influence of the movements of the electrolytes...