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Metabolism and energy.

General concept of metabolism

The release of energy occurs as a result of the oxidation of complex organic substances that make up the cells, tissues and organs of a person before the formation of simpler compounds. The consumption of these nutrients by the body is called dissimilation. Simple substances formed during the oxidation process (water, carbon dioxide, ammonia, urea) are eliminated from the body through urine, feces, exhaled air, through the skin. The process of dissimilation is in direct proportion to the energy consumption for physical labor and heat transfer.

Restoration and creation of complex organic substances of cells, tissues, human organs occurs due to simple substances of digested food. The process of accumulation of these nutrients and energy in the body is called assimilation. The process of assimilation, therefore, depends on the composition of the food, providing the body with all the nutrients.

The processes of dissimilation and assimilation occur simultaneously, in close interaction and have a common name - the process of metabolism. It consists of the exchange of proteins, fats, carbohydrates, minerals, vitamins and water metabolism.

Metabolism is directly dependent on energy consumption (for labor, heat exchange and the work of internal organs) and the composition of food.

The metabolism in the human body is regulated by the central nervous system directly and through hormones produced by the endocrine glands.
Thus, thyroid hormone (thyroxin) affects protein metabolism, pancreatic hormone (insulin) affects carbohydrate, and thyroid, pituitary, and adrenal hormones affect fat metabolism.

Daily consumption of human energy

To provide a person with food, corresponding to his energy costs and plastic processes, it is necessary to determine the daily energy consumption. Kilocalorium is considered to be the unit of measurement of human energy.

During the day, a person spends energy on the work of internal organs (heart, digestive apparatus, lungs, liver, kidneys, etc.), heat exchange and performing socially useful activities (work, study, domestic work, walks, rest). The energy expended on the work of internal organs and heat transfer is called the main exchange. At an air temperature of 20 ° C, complete rest, on an empty stomach, the basal metabolic rate is 1 kcal per 1 hour per 1 kg of human body weight. Consequently, the basal metabolic rate depends on body mass, as well as on the sex and age of the person.



Questions for self-control

1. The concept of "metabolism and energy."

2. The process of dissimilation.

3. The process of assimilation.

4. Daily consumption of human energy.
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Metabolism and energy.

  1. EXCHANGE OF SUBSTANCES AND ENERGY
    Various forms of manifestation of life are always inextricably linked with the transformation of energy. Energy metabolism is a peculiar property of every living cell. Energy-rich substances are absorbed, and the end products of metabolism with lower energy content are secreted by cells. According to the first law of thermodynamics, energy does not disappear and does not appear again. A living organism should receive
  2. Metabolism and energy
    The main feature of a living organism is metabolism and energy. In the body, there are continuous plastic growth processes, the formation of complex substances that make up the cells and tissues. In parallel, the reverse process of destruction occurs. Every human activity is associated with the expenditure of energy. The normal course of these processes requires complex organic substances, as they are
  3. EXCHANGE OF SUBSTANCES AND ENERGY IN THE HUMAN BODY
    The metabolism proceeds continuously in all cells, tissues and systems of the body and helps to maintain vital activity and preserve the constancy of the internal environment. As a result of metabolic processes are formed substances necessary for the construction of cells and tissues. Through the metabolism is provided by the entry of energy necessary for his life, is restored
  4. Some significant remarks about metabolism and energy
    The main goal with which we eat food is to get energy. We absolutely need energy for any of our actions - maintaining metabolism, constant body temperature, breathing, heartbeats, muscular work, and so on; all these processes need a constant flow of energy that is contained in food. True, not all components of food have energy, but only three.
  5. Patterns of growth of the fetus and newborn. The need for nutrients and energy.
    BALANCE OF ENERGY AND ITS CHANGES IN PERINATAL PATHOLOGY ENERGY BALANCE OF PRESENTED CHILDREN The need for energy is determined by the energy consumption of the body in these conditions. Energy consumption can be represented in the form of several components (Fig. 17-1): Еп = Еэ + Ем = Еэ + (Ес + Ер), where Еп is the total energy consumption; Еe - energy excreted (mainly with urine and feces); EH -
  6. METABOLISM
    Metabolism is the main, indispensable condition of the body's vital activity with the cessation of metabolism, biological death occurs. Metabolism is composed of two interrelated, simultaneously occurring, but opposite processes - assimilation and dissimilation. Metabolism in animals includes three stages. The initial stage is associated with the receipt, change, transformation
  7. How many human sources of energy and substance?
    It’s too early to talk about the creation of prerequisites for the development of a complete theory of human nutrition, for there has not been found a rod that would allow to unite innumerable invaluable data collected by biochemists, biophysicists, physiologists and psychologists into a coherent system. In my view, any nutrition theory can be considered as such if it answers the main question arising from the
  8. Physiological needs of the body for energy and nutrients
    With a rational balanced diet, the normal functioning of the body is possible provided that it is supplied with the necessary amount of energy corresponding to the daily energy expenditure. The daily energy inputs of the human body consist of unregulated (basic metabolism and specifically-dynamic action of food) and regulated (mental and physical activity) energy expenditure. Main
  9. The physiological needs of children of the first year of life in nutrients and energy.
    The daily need of infants in nutrients and energy depends on the age of the child, the type of feeding (natural or artificial) and the body weight of the child. Therefore, the requirements for proteins, fats, carbohydrates and energy value in the first year of life are expressed per kg of mass of heat. The need for vitamins and minerals is expressed per day. Need in
  10. Recommended Physiological Energy and Nutrient Needs
    Recommended values ​​of nutrient requirements and energy are developed taking into account gender, age and nature of work. The physiological need of the adult working-age population has been developed according to 5 groups of labor intensity depending on the magnitude of daily energy expenditure, nervous tension in the process of labor activity, its individual operations and other
  11. Metabolism
    During pregnancy, all metabolic processes are activated to meet the growing needs of the fetus, placenta, uterus, as well as the basal metabolic rate of the mother. In the process of pregnancy development, there is an intensification of protein metabolism and accumulation of protein substances in the body in order to ensure the growing fetus and the vital activity of the mother's body with plastic material.
  12. The exchange of water and minerals
    The human body is 60% water. Adipose tissue contains 20% of water (from its mass), bones - 25, liver - 70, skeletal muscles - 75, blood - 80, brain - 85%. For the normal functioning of the body, which lives in a changing environment, it is very important the constancy of the internal environment of the body. It is created by blood plasma, tissue fluid, lymph, the main part of which is water, proteins and
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