Biochemical Foundations of Human Vital Activity - Volkov, N. I., Nesen, E. N. 2000

Biochemical Foundations of Human Vital Activity
Acid-Base Balance of the Body

The functional state of the body and its capacity for physical work depend largely on the constancy of The chemical composition of its internal environment, most notably on acid-base balance.

Impairments in the acid-base balance of the internal environment during physical exertion, caused by the accumulation of acidic metabolic products, lead to a decline in physical performance and, in some cases, to the cessation of activity. Therefore, it is essential to understand the indicators of the body's acid-base state, its impact on metabolic processes, and the mechanisms that maintain acid-base equilibrium.

The internal environment of the body comprises biological fluids: Blood, Lymph, Cytosol, extracellular fluid, intestinal juice, urine, saliva, and others. They consist of approximately 90% Water, which contains dissolved or suspended chemical molecules of varying sizes and properties, their complexes, Cell Organelles, and Cells. All Components of the internal environment are in constant motion. This movement, or Transport of substances, is carried out through various mechanisms and helps maintain the constancy of the chemical composition (Homeostasis) of the body's internal environment.

Blood and the Circulatory system play a vital role in substance transport and the maintenance of homeostatic balance within the body. Driven by The Cardiovascular system, blood ensures the mass transport of chemical substances. It delivers nutrients, Vitamins, Hormones, water, minerals, and oxygen to all Cells of the body while removing Metabolic waste products from Tissues. Blood also facilitates the neutralization and elimination of acids.

The body employs various other Mechanisms for the movement of chemical substances, thereby preserving the conditions necessary for normal cellular activity and the expression of biological Functions. Transport mechanisms drive excitation processes in nerve and Muscle Tissues, Nerve Impulse transmission, the initiation and generation of Muscle contraction, the maintenance of acid-base balance, and many other processes. Let us examine the characteristics of substance transport processes in the body.



Last update: 06/08/2026

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