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absorbed absorption acid action activity already amount animal apparatus appears arrangement associated become bodies carbohydrates carbon dioxide carried causes cell-wall cells certain changes chlorophyll close complete compounds connection consequently considerable constituents construction contain continuous cortex decomposition dependent deposited described digestion direction effect energy enter evident exist extent external fact formation frequently gametophyte grains greater green growing growth increase influence intercellular known latter layer leaf leaves less light living substance material mechanism membrane nature nitrogen normal nutrition observed occur organism original oxygen particular pass plant possess present pressure probably proteid protoplasm quantity regions result roots salts secretion seeds seen side similar soil solution spaces starch stem stored stream structure subsequent sugar supply surface takes place temperature tion tissue transpiration usually vacuole varies various vegetable vessels walls whole
Page 169 - ... which goes to construct proteid, by combining with the nitrogen and sulphur absorbed in the form of salts from the soil, or with the nitrogenous residues of previous decompositions of proteid. It is supposed, however, that starch may, nevertheless, be the first visible product of the constructive metabolism ; since, unless protoplasm were being formed, no starch could be produced. This view is partly founded on the consideration...
Page 441 - ... a much divided or plumose stigma, often furnished with hairs, so that pollen falling on it may be readily » retained. On the other hand, anemophilous flowers are always inconspicuous and of a comparatively humble type. Flowers which are pollinated by insects are usually much larger and more showy, and are often very highly coloured and provided with characteristic odours. Their perianths and sometimes their sporophylls are highly modified to adapt them to the habits of their insect visitors....
Page 372 - In considering broadly the result of stimulation we must notice at the outset that it provokes a purposeful response. The living substance appears to have a definite aim...
Page 42 - Pectine swells up and dissolves in water, forming a viscous liquid which soon becomes a jelly. It exists in considerable quantity in many ripe fruits and in some mucilages. It gives no precipitate with the neutral acetate of lead, but is thrown down by the basic acetate in the form of white flocculi.
Page 167 - Sugars are what are called optically active compounds; that is, they possess the power of deflecting a ray of polarised light to the right or to the left as the latter is made to pass through either crystals or a solution of them.
Page 363 - ... the reaction of its sap is much more acid. The chloroplasts do not become green, the pigment which they contain, known as etiolin, being a pale yellow. In the leaves the differentiation of the mesophyll into palisade and spongy parenchyma does not take place.
Page 440 - ... young cuttings have sent forth their flowers. The plant, on the other hand, sent from Rio Janeiro, although treated in the same way as the other, has not flowered.* The former, although flowering freely, has not produced perfect fruit until the present year. The plants were carefully fertilised by the application of the pollen of one flower to the stigma of another. By this means we have secured a number of fruiting specimens, and I now exhibit fruiting plants with drawings of the fruit and sections....
Page 309 - We have seen that the constructive processes, partly anabolic and partly katabolie, are much greater than those which lead to the disappearance of material from the plant-body. The result of this is that there is a conspicuous increase in the substance of the plant, as well as an accumulation of potential energy which can be made use of by the plant through various decompositions which its protoplasm can set up. The great permanent accumulation of material is what we associate with the processes...
Page 355 - Each band is in a particular phase of its rhythm at any given moment, and the successive bands follow one another through the phases of their rhythm in orderly sequence, so that when one is at its maximum, another diametrically opposite to it is at its minimum. The phases of maximum and minimum turgidity thus pass rhythmically round the organ, and the apex is consequently compelled to describe ii spiral line as it grows.