Homeostasis is an organism's process of maintaining a stable internal environment suitable for sustaining life. The word homeostasis derives from Greek, with. Learn about homeostasis, the regulation of conditions in the body such as temperature, water content and carbon dioxide levels. biology; microscope. biology: Homeostasis. The concept of homeostasis—that living things maintain a constant internal environment—was first suggested in the.


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Homeostasis biology the hypothalamus detects a hypertonic extracellular environment, it causes the secretion of an antidiuretic hormone ADH called vasopressin which acts on the effector organ, which in this case is the kidney. The effect of vasopressin on the kidney tubules is to reabsorb water from the distal convoluted tubules and collecting ductsthus preventing aggravation of the water loss via the urine.

The homeostasis biology simultaneously stimulates the nearby thirst center causing an almost irresistible if the hypertonicity is severe enough urge to drink water.

Homeostasis - Definition and Examples | Biology Dictionary

The cessation of urine flow prevents the hypovolemia and hypertonicity from getting worse; the drinking of water corrects the defect. Hypo-osmolality results in very low plasma ADH levels. This results in homeostasis biology inhibition of water reabsorption from the kidney tubules, causing high volumes of very dilute urine to be excreted, thus getting rid of the excess water in the body.

Urinary water loss, when the body water homeostat is intact, is a compensatory water loss, correcting any water excess in the body.


However, since the kidneys cannot generate water, the homeostasis biology reflex is the all important second effector mechanism of the body water homeostat, correcting any water deficit in the body. Acid—base homeostasis and Acid-base imbalance The plasma pH can be altered by respiratory changes in the partial pressure of carbon dioxide; or altered by metabolic changes in the carbonic acid to bicarbonate ion ratio.

The bicarbonate buffer system regulates the ratio of carbonic acid to bicarbonate to be equal to 1: A change in the plasma pH gives an acid—base imbalance. In acid—base homeostasis there are two mechanisms that can help regulate the pH.

Respiratory compensation a mechanism of the respiratory centeradjusts the partial pressure of carbon dioxide by changing homeostasis biology rate and depth of breathing, to bring the pH back to normal.

The partial pressure of carbon dioxide also determines the concentration of carbonic acid, and the bicarbonate buffer system can also come into play.

Renal compensation can help the bicarbonate buffer system. The sensor for the plasma bicarbonate concentration is not known for certain. It is very probable that the renal tubular cells of the distal convoluted tubules are themselves sensitive to the pH of the plasma.

Bicarbonate ions are simultaneously secreted into the blood that decreases the carbonic acid, and consequently raises the plasma pH. When hydrogen ions are excreted into the urine, and bicarbonate into homeostasis biology blood, the latter combine with the excess hydrogen ions in the plasma that stimulated the kidneys to perform this operation.


The resulting reaction in the plasma is the formation of carbonic acid which is in equilibrium with the plasma partial pressure of carbon dioxide. The two types of systems are alike, however, in their goals—to sustain activity within prescribed ranges, whether to control the thickness of rolled steel or the pressure within the circulatory system.

The control of body temperature in humans is a good example of homeostasis in a biological system. Feedback about body temperature is carried through the bloodstream to the brain and results in compensatory adjustments in the breathing rate, the level of blood sugarand the metabolic homeostasis biology.

Heat loss in humans is aided by reduction of activity, by perspirationand by heat-exchange mechanisms that permit larger amounts of blood to circulate near the skin surface. Heat loss is reduced by insulation, decreased circulation to the skin, and cultural modification such as the use of clothing, shelter, and external heat sources.


Homeostasis biology normally think about homeostasis in terms of the whole body, but individual systems — that is, groups of organs — also maintain homeostatic conditions.

Nonetheless, prolonged imbalance in just one system can negatively impact the homeostasis of the entire organism. Examples of Homeostasis Homeostasis is a regulatory procedure. In the homeostasis biology body, homeostatic processes regulate: