What is the metabolism in biology: the definition

An indispensable condition for the existence of any living organism is the constant supply of nutrients and the elimination of the final products of decay.

What is the metabolism in biology?

Metabolism, or metabolism, is a special set of chemical reactions that take place in any living organism to support its activity and life. Such reactions give the body the ability to develop, grow and multiply, while maintaining its structure and responding to environmental stimuli.

Metabolism is usually divided into two stages: catabolism and anabolism. At the first stage, all complex substances are split and become more simple. On the second, together with the energy costs, nucleic acids, lipids and proteins are synthesized.

The most important role in the metabolic process is played by enzymes, which are active biological catalysts. They are able to reduce the activation energy of the physical reaction and regulate the metabolic pathways.

Metabolic chains and components are absolutely identical for many species, which is proof of the unity of origin of all living beings. This similarity shows a comparatively early appearance of evolution in the history of the development of organisms.

Classification by type of metabolism

What is the metabolism in biology is described in detail in this article. All living organisms that exist on planet Earth can be divided into eight groups, being guided by the source of carbon, energy and oxidized substrate.

Living organisms can use the energy of chemical reactions or light as a source of nutrition. As an oxidizable substrate, there can be both organic and inorganic substances. The source of carbon is carbon dioxide or organic matter.

There are microorganisms that, being in different conditions of existence, use a different type of metabolism. It depends on humidity, lighting and other factors.

Multicellular organisms can be characterized by the fact that the same organism can have cells with different types of metabolic processes.

Catabolism

Biology metabolism and energy is treated through such a concept as "catabolism." This term is called metabolic processes, during which large particles of fats, amino acids and carbohydrates are split. During the catabolism, simple molecules appear that participate in biosynthetic reactions. It is thanks to these processes that the body is able to mobilize energy, turning it into an accessible form.

In organisms that live by photosynthesis (cyanobacteria and plants), the electron transfer reaction does not release energy, but accumulates, thanks to sunlight.

In animals, catabolism reactions are associated with the splitting of complex elements to simpler ones. Such substances are nitrates and oxygen.

Catabolism in animals is divided into three stages:

1. Splitting of complex substances to simpler ones.
2. Splitting of simple molecules to even simpler ones.
3. The release of energy.

Anabolism

Metabolism (biology of the 8th class considers this concept) is characterized by anabolism - a set of metabolic processes of biosynthesis with energy expenditure. Complex molecules, which are the energy basis of cellular structures, are consistently formed from the simplest predecessors.

First, amino acids, nucleotides and monosaccharides are synthesized. Then the above elements become active forms due to ATP energy. And at the last stage all active monomers combine into complex structures, such as proteins, lipids and polysaccharides.

It is worth noting that not all living organisms synthesize active molecules. Biology (metabolism is described in detail in this article) identifies such organisms as autotrophs, hemotrophs and heterotrophs. They receive energy from alternative sources.

Energy derived from sunlight

What is the metabolism in biology? The process by which there is all life on Earth, and distinguishing living organisms from inanimate matter.

The energy of sunlight is fed by some protozoa, plants and cyanobacteria. In these representatives, metabolism is due to photosynthesis - the process of oxygen uptake and the release of carbon dioxide.

Digestion

Such molecules as starch, proteins and cellulose are cleaved even before they are used by cells. In the process of digestion, special enzymes take part that split proteins to amino acids, and polysaccharides to monosaccharides.

Animals can isolate such enzymes only from special cells. But microorganisms such substances are released into the surrounding space. All substances that are produced by extracellular enzymes, enter the body with the help of "active transport".

Control and regulation

What is the metabolism in biology, you can read in this article. Each organism is characterized by homeostasis - the constancy of the internal environment of the body. The presence of such a condition is very important for any organism. Since all of them are surrounded by an environment that is constantly changing, in order to maintain optimal conditions within the cells, all metabolic reactions must be properly and precisely regulated. A good metabolism makes it possible for living organisms to constantly contact the environment and respond to its changes.

Historical background

What is the metabolism in biology? The definition is at the beginning of the article. The concept of "metabolism" was first used by Theodore Schwann in the forties of the nineteenth century.

Scientists have been studying the metabolism for several centuries, and it all began with attempts to study animal organisms. But the term "metabolism" was first used by Ibn al-Nafisa, who believed that the whole body is constantly in a state of nourishment and decay, so it is characterized by constant changes.

The biology lesson "Metabolism" will open the whole essence of this concept and describe examples that will help to increase the depth of knowledge.

The first controlled experiment on the study of metabolism was received by Santorio Santorio in 1614. He described his condition before and after eating, working, drinking water and sleeping. He was the first to notice that most of the food consumed was lost during the "inconspicuous evaporation" process.

In the initial studies, metabolic reactions were not detected, and scientists believed that the living tissue is controlled by a living force.

In the twentieth century, Eduard Buchner introduced the concept of enzymes. Since then, the study of metabolism began with the study of cells. During this period, biochemistry became a science.

What is the metabolism in biology? Definition can be given the following - this is a special set of biochemical reactions that support the existence of the organism.

Minerals

Inorganic substances play a very important role in metabolism. All organic compounds consist of a large amount of phosphorus, oxygen, carbon and nitrogen.

Most inorganic compounds allow you to control the level of pressure inside the cells. Also, their concentration positively affects the functioning of the muscle and nerve cells.

Transition metals (iron and zinc) regulate the activity of transport proteins and enzymes. All inorganic microelements are absorbed by transport proteins and never remain in a free state.