HUMAN BIOCHEMISTRY - L. V. Kapilevich - 2016

PART 1. SPORTS BIOCHEMISTRY

GENERAL CHARACTERISTICS OF METABOLISM

Metabolic processes occurring in the body can be conditionally divided into two stages: Digestion and METABOLISM.

Digestion

During digestion, dietary nutrients are broken down by digestive Enzymes and converted into simple compounds that are universal for All living organisms. Therefore, the End products of digestion can enter the body's internal environment and be utilized by Cells for various purposes.

Metabolism

Metabolism is the totality of Chemical Reactions taking place in the internal environment of the body, i.e., within its cells.

In turn, metabolism is divided into Catabolism and anabolism. Catabolism involves chemical reactions in which large molecules are broken down and converted into smaller ones. The end products of catabolism are such simple substances as СО₂, Н₂О, and NН₃.

Catabolism is characterized by the following patterns:

✵ oxidation reactions predominate;

✵ it proceeds with the consumption of oxygen;

✵ energy is released, half of which is stored as the chemical energy of adenosine triphosphate (ATP). The other part of the energy is dissipated as heat.

Anabolism includes a variety of synthesis reactions.

Anabolism is characterized by the following features:

✵ reduction reactions are typical;

✵ hydrogen consumption occurs;

✵ it proceeds with the consumption of energy, the source of which is ATP.

Main Purpose of Metabolism

The simultaneous occurrence of Catabolic and anabolic reactions leads to the renewal of the body's chemical composition, which is a prerequisite for its vital activity. When anabolism prevails over catabolism, chemical substances accumulate in the body, primarily Proteins. The accumulation of proteins in the body is a prerequisite for its GROWTH AND DEVELOPMENT. In addition, metabolism provides energy (in the form of ATP molecules) to meet all the body's needs.

Integration of Metabolism

Catabolism and anabolism, which form a unified metabolic system, are characterized by:

✵ the presence of common intermediates in the majority of metabolic pathways;

✵ the possibility of interconversion via common metabolites;

✵ The Use of common Coenzymes and the necessity for their continuous Circulation;

✵ the presence of a common catabolic pathway and a unified system for energy release and utilization (Respiratory Chain);

✵ the presence of similar regulatory mechanisms.

QUESTIONS FOR SELF-Control

1. Define The process of digestion.

2. What patterns are characteristic of catabolic reactions in The Human Body?

3. What patterns are characteristic of anabolic reactions in the human body?

4. What is the primary purpose of metabolism?

5. Which substances are the simplest end products of catabolism?

6. What determines the integration of metabolism?