basal metabolism


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metabolism

 [mĕ-tab´o-lizm]
2. the sum of the physical and chemical processes by which living organized substance is built up and maintained (anabolism), and by which large molecules are broken down into smaller molecules to make energy available to the organism (catabolism). Essentially these processes are concerned with the disposition of the nutrients absorbed into the blood following digestion.

There are two phases of metabolism: the anabolic and the catabolic phases. The anabolic, or constructive, phase is concerned with the conversion of simpler compounds derived from the nutrients into living, organized substances that the body cells can use. In the catabolic, or destructive, phase these organized substances are reconverted into simpler compounds, with the release of energy necessary for the proper functioning of the body cells.

The rate of metabolism can be increased by exercise; by elevated body temperature, as in a high fever, which can more than double the metabolic rate; by hormonal activity, such as that of thyroxine, insulin, and epinephrine; and by specific dynamic action that occurs following the ingestion of a meal.

The basal metabolic rate refers to the lowest rate obtained while an individual is at complete physical and mental rest. Metabolic rate usually is expressed in terms of the amount of heat liberated during the chemical reactions of metabolism. About 25 per cent of all energy from nutrients is utilized by the body to carry on its normal function; the remainder becomes heat.
basal metabolism the minimal energy expended for the maintenance of respiration, circulation, peristalsis, muscle tonus, body temperature, glandular activity, and the other vegetative functions of the body.

ba·sal me·tab·o·lism

oxygen used by a subject during minimal physiologic activity while awake; an obsolete test determined by measuring oxygen consumption of a fasting subject at complete bodily and mental rest and a room temperature of 20°C.

basal metabolism

n. Abbr. BM
The minimum amount of energy required to maintain vital functions in an organism at complete rest, measured by the basal metabolic rate in a fasting individual who is awake and resting in a comfortably warm environment.

ba·sal me·tab·o·lism

(BM) (bāsăl mĕ-tabŏ-lizm)
Oxygen used by a subject during minimal physiologic activity while awake; a test determined by measuring oxygen consumption of a fasting subject at complete bodily and mental rest and a room temperature of 20°C.

basal metabolism

The minimum amount of energy needed to maintain the vital functions-heart beat, respiration and digestion-in a person at complete rest.
References in periodicals archive ?
Basal metabolism and creatnine excretion in different physiological groups.
Basal Metabolism in pregnant and nursing women and children.
Litopenaeus vannamei juveniles, as many species of crustaceans, showed a biochemical adaptation response to an absence of food (decrease of digestive enzyme activities) using their own reserves (hepatopancreatic glycogen, protein, and probably lipids, estimated through O:N ratio variations) for homeostasis and to channel enough energy for basal metabolism in that period (Cuzon and Ceccaldi 1973, Dall and Smith 1986; Dall and Smith 1987, Leung et al.
They possess a similar level of digestive enzyme activities; then, there are good reasons, according to values of metabolism rates obtained in this study, to think that tropical species present a higher basal metabolism and activity that leaves them more dependent on regular food supply for their development.
based on work on dogs (16.6 kg) and sea otters (18.4 kg; Enhydra lutris), we assumed that postprandial resting metabolism was 50% higher than basal metabolism (Costa and Kooyman 1984, Diamond et al.
It is well known that the metabolism of fed animals during the active period is somewhat higher than basal metabolism (e.g., Karasov 1981).
(18) A further advantage of exercise is that while a diet alone reduces basal metabolism, exercise during dieting actually increases basal metabolism and post-exercise energy expenditure.
(29) Diet programs such as Atkins and others vary the diet in both content and caloric composition in an attempt to trick metabolism and by increasing basal metabolism and reducing caloric intake, causing a reduction in body weight.
The data on body masses and mass-specific rates of basal metabolism were taken from the reviews by McNab (1988a) and Elgar and Harvey (1987), with additional data from Altman and Ditmer (1974), and are presented in table 1.
Percentage of distribution of total variance of the dependent variable (mass-specific rate of basal metabolism, BM) explained by each of the independent variables (body mass, BW, and genome size, GS) in a multiple-regression model (BM = a + b*BW + c*GS) at different taxonomic levels.
The normal daily calorie intake depends on the basal metabolism rate and the activity factor.