✅ Definition:
Homeostasis is the process by which living organisms maintain a stable internal environment despite changes in external conditions. This dynamic balance is essential for survival and proper functioning of cells, tissues, and organs.
📜 Origin of the Term:
The term “homeostasis” was coined by American physiologist Walter Cannon in 1926. It derives from Greek: “homeo” meaning “similar” and “stasis” meaning “standing still” or “stability.”
🔬 How Homeostasis Works:
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Sensors/Receptors: Detect changes (stimuli) in the internal or external environment (e.g., temperature, pH, glucose levels).
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Control Center: Usually the brain or endocrine glands, which process the information and determine the response.
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Effectors: Organs or cells that act to correct the imbalance and restore conditions to the normal range.
⚙️ Key Parameters Regulated by Homeostasis:
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Body temperature
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Blood glucose levels
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Blood pressure
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pH balance of blood and fluids
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Water and electrolyte balance
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Oxygen and carbon dioxide levels
🧠 Examples:
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Thermoregulation: When body temperature rises, mechanisms like sweating and vasodilation cool the body; when it drops, shivering and vasoconstriction conserve heat.
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Blood sugar regulation: Insulin and glucagon hormones regulate glucose concentration in the blood.
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pH regulation: The respiratory system and kidneys work together to maintain acid-base balance.
⚠️ Importance:
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Ensures cells operate within optimal conditions.
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Prevents damage caused by extreme fluctuations.
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Supports metabolic processes and overall health.
🔮 Disruptions and Diseases:
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Failure in homeostasis can lead to diseases like diabetes (blood sugar imbalance), hyperthermia or hypothermia (temperature imbalance), and acidosis or alkalosis (pH imbalance).