Dissimilation


Also found in: Dictionary, Thesaurus, Medical, Wikipedia.

Dissimilation

 

in biology, the opposite of assimilation in the process of metabolism, consisting in the decomposition of organic compounds and conversion of protein, nucleic acids, fats, and carbohydrates (including those ingested) into simple substances. A number of dissimilation processes—respiration, fermentation, and glycolysis—play the central role in metabolism. As a result of these processes, energy contained in the molecules of complex organic compounds is released, partially to be transformed into adenosinephosphoric acids (chiefly ATP). The fundamental end products of dissimilation in all organisms are water, carbon dioxide, and ammonia. In animals these products are eliminated as they accumulate. In plant organisms CO2, partially, and NH3, totally, are used in the biosynthesis of organic matter, thus serving as the primary materials for assimilation.

The inseparable link between dissimilation and assimilation assures constant tissue renewal in organisms. Thus, in human blood one-half of the existing albumin is exchanged for new albumin molecules in ten days; the life span of erythrocytes is about four months. The relationship of the intensity of assimilation and dissimilation changes in relation to the stage of development, age, and physiological condition of the organism. The growth and development of the organism are characterized by the predominance of assimilation, which is manifested in the formation of new cells, tissues, and organs; their growth and differentiation; and in a general increase in body weight. In some pathological conditions and in starvation dissimilation usually predominates over assimilation, leading to a decrease in body weight.

S. E. SEVERIN and G. A. SOLOV’EVA


Dissimilation

 

in linguistics, one of the kinds of combinative sound changes in the course of speech. It occurs when one of two identical or similar speech sounds (adjacent or nonadjacent) changes to another distinct or less similar sound. Two examples of dissimilation are Latin peregrinum and Russian piligrim and Latinfebruaris and Russian fevral’.

References in periodicals archive ?
It is worth mentioning that sugar dissimilation alone in the liquor during the pretreatment does not evaluate the process efficiency because it could be affected by the saccharification of the hexoses present, mainly in the cellulosic fraction, indicating the need of further enzymatic hydrolysis or characterization of the resulting solid fraction.
We can add here that the dissimilation between the second and the third duration is not so clear in Koidula's T4 as it is in Kreutzwald's: in positions a1 and [[alpha].
It is beside my point here, but I cannot resist the temptation to mention that if the Kurdistan Workers' Party (PKK) establishes its tiny Kurdistan in the Southeast, the first thing it will do is employ forced and inhumane assimilation and dissimilation to create a culturally and linguistically homogenous nation, similar to Kemalistan in the 1930s.
The exponential growth of legal literature, interdisciplinary nature of law subjects, their relationship & interdependence, widespread legal research activities and rapid dissimilation of legal research products are the main reasons distinguishing law faculty members from the rest of the social sciences researchers and faculty members, therefore, investigation of their information needs and seeking behavior is very much important.
Apres son election, le President de la Republique, Nicolas Sarkosy, rebondit sur quelques cas particulierement mediatises (1) pour justifier la necessite d'une intervention legislative tres controversee, d'abord concue pour les signes religieux et entre tous le voile integral, mais finalement elargie a toute forme de dissimilation du visage dans l'espace public (2).
involves both assimilation and dissimilation, superiority and inferiority, violence and healing, and their inversion.
See Timur Kuran, "Ethnic Dissimilation and Its International Diffusion," in The International Spread of Ethnic Conflict: Fear, Diffusion, and Escalation, ed.
Thus, the use of traditional measures for dissimilation was not appropriate, which was also the case in the Euclidean distance, as it was not yet possible to affirm that the individuals of a pair had close values (CRUZ; CARNEIRO, 2003).
That is why one can argue that the need to exert physical activity - viewed as a means of physical education and sport, whether professional or amateur - is also a biological need that is integrated in man's various organic necessities, as are those "linked to the assimilation and dissimilation process, or anabolism and catabolism, such as hunger, thirst and breathing, on one hand, and the necessity to preserve the species, or sexual instinct, on the other.
1998), to assess the relationship between N assimilation and dissimilation by soil microbial biomass (Dijkstra et al.
By doing so, a school wide dissimilation of values among students can be achieved in a subtle manner.
3-HPA is not an end product of the bacterial glycerol dissimilation, but an intermediate compound that must be trapped by semicarbazide, which reduces its toxic affect on living cells and prevents its further reduction to 1,3-PDO, increasing the yield of 3-HPA production (Abeles et al.