Subject and Tasks of Physiology

What normal physiology studies

Normal physiology is the science of health. Its subject is the functions and processes occurring in a living organism, the regulatory mechanisms of these processes, as well as adjustment (adaptation) to a constantly changing external and internal environment. The discipline examines vital activity at all possible levels of biological systems: cellular, tissue, organ, systemic, and organismal.

The main goal of normal physiology is to study the patterns of health formation and the activity of physiological systems. Special attention is paid to their role in ensuring and maintaining the normal level of various constants. These constants include blood norms, as well as physical, mechanical, and chemical parameters.

The object of physiology in a broad sense is the animal and human organism. However, the object of normal (medical) physiology specifically is exclusively the human organism.

Main tasks of physiology

Physiology faces a number of large-scale tasks that determine the development of clinical medicine:

• Establishing the foundation of medicine, which serves as the basis for the diagnostics and prevention of various conditions.
• Developing specialized methods aimed at enhancing the functional reserves of the organism.
• Formulating the concept of regulatory mechanisms and health maintenance.
• Deep study of the mechanisms of human adaptation to factors of both internal and external environments.
• Developing the theory of physiological experiment, which forms a separate branch — experimental physiology.
• Developing methods of clinical and physiological research necessary for related clinical disciplines.

Pathophysiology: when the norm is disrupted

If normal physiology studies health, then pathological physiology is the science that investigates the causes and mechanisms of the onset, development, course, and outcome of diseases, as well as their general patterns. Its subject is not the sick organism itself, but the concept of "disease" and all its components.

Pathophysiology studies functional changes in a sick body, actively using the experimental method. Its tasks include establishing the essence of the disease, studying the conditions of its occurrence, uncovering the mechanisms of its course, and determining the principles of treatment and prevention. The discipline includes three sections:

1. General nosology — the general doctrine of disease.
2. Typical pathological processes — standard reactions of the organism.
3. Pathophysiology of organs and systems — specific pathophysiology.

Biochemistry: chemical foundations of physiology

Physiological processes are based on chemical reactions. Biochemistry studies the substances of living organisms, their transformations, and the connection of these transformations with organ activity. The science emerged about a hundred years ago at the interface of physiology and organic chemistry, and the term itself was introduced in 1903 by Carl Neuberg.

According to the nature of research, biochemistry is divided into static (structure and composition), dynamic (metabolism and energy exchange), and functional (the connection of chemistry with physiological functions). By objects of study, human and animal biochemistry, plant biochemistry, and the biochemistry of microorganisms and viruses are distinguished.

The subject of medical biochemistry is man. Its goals include studying the molecular foundations of functions and the pathogenesis of diseases, as well as biochemical methods of diagnosis, treatment, and monitoring. The cure of any pathology implies the normalization of impaired biochemical processes.

Microbiology in the context of physiology

The physiological state of the organism is influenced by microbes. Microbiology (the name was proposed by P.É. Duclaux, although L. Pasteur proposed the term "microbia") studies their systematics, morphology, physiology, genetics, and ecology. The science investigates the relationships of microbes with other life forms, the pathogenesis of infections, and develops methods for their diagnosis, treatment, and prevention.

Since the size of bacteria is about 1 µm, and viruses up to 200 nm (overall, most microbes do not exceed 0.1 mm), they are studied using light and electron microscopy.

Class and exam questions

What else to study on this topic

• Levels of organization of biological systems (from cell to organism)
• Physiological constants: blood norms, physical and chemical parameters
• Sections of biochemistry: static, dynamic, and functional
• Goals and objectives of the medical biochemistry course
• Systematics and morphology of microorganisms

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.