Energy exchange

Metabolism is an integral component of the body's vital activity. It includes several processes. Energy exchange involves the splitting of organic substances and the release of energy from chemical compounds and bonds. It is noted that its further distribution is carried out by a part in the form of heat. The other part is reserved in ATP molecules.

Stages of energy metabolism in animals

The first stage is preparatory. Energy metabolism begins with the penetration of food into the human body or animal in the form of complex high-molecular elements. Before penetrating into tissues and cells, these compounds break down to low molecular weight.

Hydrolytic cleavage of organic substances is carried out with the participation of water. This process takes place in the digestive tract (in multicellular), at the cellular level (in lysosomes), in the digestive vacuoles (in unicellular) under the influence of certain enzymes.

Proteins in humans and animals are split in the duodenum and stomach to amino acids. This process occurs under the influence peptidrolrol (chemotripsin, trypsin, pepsin). In the oral cavity the process of cleavage of polysaccharides begins. The enzyme ptyalin takes part in this. Further cleavage of polysaccharides occurs under the influence of amylase in the duodenum. Here there is a splitting of fats. This process is affected by lipase. The energy that is released after this is distributed in the form of heat.

Energy metabolism involves the supply of nutrients in the blood and transport them to all cells and organs. In cells, they penetrate directly into the cytoplasm or the lysosome. In the event that substances are cleaved in the lysosomes at the cellular level, they are immediately delivered to the cytoplasm. This stage involves the preparation of compounds for intracellular cleavage.

In the second stage, the energy exchange is anoxic oxidation. Processes in this case occur without the participation of oxygen, at the cellular level. Oxidation occurs in the cell cytoplasm. One of the key elements that ensure energy metabolism is glucose. Other organic compounds (amino acids, glycerol, fatty acids) are included in the process of its transformation at different stages.

The cleavage of glucose without the participation of oxygen is called glycolysis. This connection undergoes several successive transformations. First, it converts to fructose. Glucose is phosphorylated - activated by the action of two ATP molecules, turning into fructose-diphosphate. The field of this is the decomposition of the molecule of hexavalent carbon into two three-carbon molecules of glycerophosphate. As a result of several reactions, their oxidation takes place. In this case, the molecules lose two hydrogen atoms, eventually becoming molecules of pyruvic acid. The result of these reactions is four synthesized ATP molecules. Since two ATP molecules were used for initial glucose activation, 2ATF is generally formed. Thus, the energy released during the splitting of glucose is partially reserved, and partially released in the form of heat.

At the third stage, breathing takes place (biological oxidation). This stage is possible only under the influence of oxygen. In this regard, it is called oxygen. This process takes place in the mitochondria.

Under conditions of a general (basic) exchange, the energy costs (on average) for an adult are about 24 kcal / kg / day. When calculating the average person, the daily consumption is 1500 kcal for women and about 1700 kcal for men. In patients with a different pathology profile, the need for energy per day can increase two to three times.