Brain Primer

The Body in Balance: Homeostasis

  • Reviewed18 Oct 2022
  • Author Diane A. Kelly
  • Source BrainFacts/SfN
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The cells of your body are immersed in a constantly changing environment. The nutrients that sustain them rise and fall with each meal. Gases, ions, and other solutes flow back and forth between your cells and blood. Chemicals bind to cells and trigger the building and release of proteins. Your cells digest food, get rid of waste, build new tissues, and destroy old cells. Environmental changes, both internal and external, ripple through your body’s physiological systems. One of your brain’s less-visible jobs is to cope with all these changes, keep them within a normal range, and maintain the healthy functions of your body.

The tendency of your body’s tissues and organ systems to maintain a condition of balance or equilibrium is called homeostasis. Homeostasis depends on active regulation, with dynamic adjustments that keep the environment of your cells and tissues relatively constant. The brain is part of many homeostatic systems, providing signals that coordinate your body’s internal clocks and regulating hormone secretion by the endocrine system. These functions often involve a region of the forebrain called the hypothalamus, a command center that regulates the activities of internal organs, among many other functions.

Adapted from the 8th edition of Brain Facts by Diane A. Kelly.



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