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Human homeostasis (homeostasis is from Greek: ὅμοιος homoios, "similar" and στάσις stasis, "standing still") is the property of homeostasis within the human body. The human body manages a multitude of highly complex interactions to maintain balance or return systems to functioning within a normal range. These interactions within the body facilitate compensatory changes supportive of physical and psychological functioning. This process is essential to the survival of the person and to our species. The liver, the kidneys, and the brain (hypothalamus, the autonomic nervous system and the endocrine system〔() Reference for autonomic and endocrine system.〕) help maintain homeostasis. The liver is responsible for metabolizing toxic substances and maintaining carbohydrate metabolism. The kidneys are responsible for regulating blood water levels, re-absorption of substances into the blood, maintenance of salt and ion levels in the blood, regulation of blood pH, and excretion of urea and other wastes. An inability to maintain homeostasis may lead to death or a disease, a condition known as ''homeostatic imbalance''. For instance, heart failure may occur when negative feedback mechanisms become overwhelmed and destructive positive feedback mechanisms take over.〔Marieb, Elaine N. & Hoehn, Katja (2007). ''Human Anatomy & Physiology'' (Seventh ed.). San Francisco, CA: Pearson Benjamin Cummings.〕 Other diseases which result from a homeostatic imbalance include diabetes, dehydration, hypoglycemia, hyperglycemia, gout and any disease caused by the presence of a toxin in the bloodstream. Medical intervention can help restore homeostasis and possibly prevent permanent damage to the organs. ==Temperature== (詳細はwarm-blooded, maintaining a near-constant body temperature. Thermoregulation is an important aspect of human homeostasis. Heat is mainly produced by the liver and muscle contractions. Humans have been able to adapt to a great diversity of climates, including hot humid and hot arid. High temperatures pose serious stresses for the human body, placing it in great danger of injury or even death. In order to deal with these climatic conditions, humans have developed physiologic and cultural modes of adaptation. Temperature may enter a circle of positive feedback, when temperature reaches extremes of 45°C (113°F), at which cellular proteins denature, causing the active site in proteins to change, thus causing metabolism stop and ultimately death. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Human homeostasis」の詳細全文を読む スポンサード リンク
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