Assimilation (redirected from Assimilation (disambiguation))

assimilation [ə‚sim·ə′lā·shən]

(geology)

Incorporation of solid or fluid material that was originally in the rock wall into a magma.

(physiology)

The conversion of nutritive materials into protoplasm.

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Assimilation 

in physiology, the living organism’s utilization of food for the expenditure of energy and for restorative body functions. Complex food substances are assimilated after being broken down into simple compounds by the digestive enzymes. The effective degree of assimilation is determined by the difference between the body’s alimentary intake of proteins, fats, and carbohydrates and the end products resulting from their breakdown. The important factor in assimilation is not the absolute degree of digestibility but the rate at which food substances are digested, which may limit subsequent absorption.

The degree of assimilation depends on the nutritional regimen, food content, method of culinary preparation, and gastrointestinal tract functioning. The capacity to assimilate is lowered when the nutritional regimen is disrupted or when the stomach is overloaded with large quantities of food. Animal food products are assimilated more completely than vegetable products. The human body assimilates 92 to 96 percent of the proteins of animal origin, 46 to 70 percent of those from vegetables, 98 percent of the carbohydrates, and 95 percent of the fats ingested. The physiological value of food is largely determined by its assimilability, which must be taken into account in establishing nutritional norms. Unassimilable food substances, and especially cellulose, play an essential part in the movements of the intestine.

REFERENCES

McDonald, P., R. Edwards, and D. Greenhalge. Pitanie zhivotnykh. Moscow, 1970. (Translated from English.)
Fiziologiia pishchevareniia. Leningrad, 1974. (Manual of physiology.)
Chernikov, M. P. Proteoliz i biologicheskaia tsennost’ belkov. Moscow, 1975.
Handbook of Physiology, vol. 1, sec. 6: Alimentary Canal. Washington, 1967.
Intestinal Absorption and Malabsorption. Basel-New York, 1968.

G. M. ROSHCHINA and A. M. UGOLEV