Homeostasis and Adaptability

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Homeostasis and Adaptability
Both these properties of living systems are regulated by the control system. In order to function normally, unicellular and multicellular organisms must maintain a relatively constant internal environment under considerably varying conditions in the external environment.

Homeostasis and mechanisms of its regulation are better known in mammals, especially in humans. These organisms maintain the level of many physicochemical parameters in their fluids constant (see later section "Homeostasis - The maintenance of Constant Internal Environment is Prerequisite of Living Systems", in this chapter). Among the most important homeostatic parameters they regulate are body temperature, pH, levels of electrolytes, hormones, growth factors, secreted proteins, etc. So, for example, in winter when the external temperature falls, in warm-blooded animals, a specialized part of the controller of their control system, the hypothalamus, activates neuroendocrine mechanisms to increase heat generation. On the other hand, in the summer when the environmental temperature rises above the normal body temperature, it activates mechanisms that reduce heat production and increase heat loss. Living organisms can respond adaptively to changes in the environment with changes in their structure, function, behavior, and life history that tend to neutralize the harmful
effects of environmental changes or agents and maintain homeostasis.

Numerous described cases of developmental plasticity, both intragenerational and transgenerational
(see Chapter 4), illustrate the high capability of living systems to adapt and survive even under unfavorable environmental conditions. The adaptability increased the independence of living systems from their environment. The above properties are unique to living systems, and the control system is fundamental to all of them: reproduction, growth, evolution, adaptability, and evolution. An organism can live without reproducing, evolving, or growing for considerable spans of time, from a few minutes for a bacterium, to one century for a human being, to thousands of years for some trees. But any human being would almost instantly perish in the absence of the control system. From this view, all the essential properties and functions of living systems are subordinate to the control system. Advertisement