Читать книгу The Body at Work: A Treatise on the Principles of Physiology онлайн

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Glycogen is stored in the liver. Fat, if it is assimilated in excess of the needs of the body, accumulates in the connective tissues. Proteins, if in excess, are either destroyed by oxidation, or partly destroyed and partly converted into fat. Increasing the amount and richness of the food does not, if nutrition is already at its best, improve the quality of the blood. The surplus of food is either stored or burnt. The composition of lymph is unaffected. Its quality is not improved by taking more food than enough. A perfect balance is maintained. Every cell is able, when conditions are normal, to obtain as much nutriment as it needs. It cannot get more. It cannot lay by food and shirk work. If it did it would grow. Reaching its optimum size, it would divide. Additional tissue would be formed. But when it does more work it needs more food; and it is a matter of common experience that the system is so adjusted that food is supplied to the tissues, not reluctantly, but with a slight tendency towards generosity. Working harder than usual, they find the lymph by which they are bathed somewhat richer in the materials that they need than the necessities of the case demand. They are able not merely to obtain all they want, but a little more. Activity favours growth.