en>Chris the speller: per WP:HYPHEN, sub-subsection 3, points 3,4,5, replaced: commonly- → commonly , currently- → currently using AWB

2013-08-18T01:39:21Z

per WP:HYPHEN, sub-subsection 3, points 3,4,5, replaced: commonly- → commonly , currently- → currently using AWB

← Older revision		Revision as of 03:39, 18 August 2013
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	The ~~writer~~'s title is ~~Christy Brookins~~. ~~For years he~~'s ~~been living~~ in ~~Alaska~~ and ~~he doesn~~'~~t plan on altering it~~. ~~One~~ of the ~~extremely best things in~~ the ~~world for him~~ is ~~performing ballet and he'll be beginning some thing else alongside with it~~. ~~Office supervising~~ is ~~my occupation~~.<br><br>~~my web blog~~: ~~real psychics~~ [[http://www.~~skullrocker~~.com/~~blogs~~/~~post~~/~~10991 Read the Full Post~~]]		{{Refimprove\|date=December 2010}}<br>
			{{Acids and bases}}
			'''Acid–base homeostasis''' is the part of [[human homeostasis]] concerning the proper balance between [[acid]]s and [[Chemical base\|bases]], also called body [[pH]]. The body is very sensitive to its pH level, so strong mechanisms exist to maintain it. Outside the acceptable range of pH, [[protein]]s are denatured and digested, [[enzyme]]s lose their ability to function, and [[death]] may occur.

			==Mechanism==
			[[File:Acid-base nomogram.svg\|thumb]]
			The body's acid–base balance is normally tightly regulated by buffering agents, the respiratory system, and the renal system, keeping the arterial blood pH between 7.38 and 7.42.<ref>{{MedlinePlusEncyclopedia\|003855\|Blood gases}}</ref><ref>{{cite book\|last=Caroline\|first=Nancy\|title=Nancy Caroline's Emergency care in the streets\|edition= 7th\|year=2013\|publisher=Jones & Bartlett Learning\|location=Buffer systems\|isbn=978-1449645861\|pages=347-349}}</ref> Several [[buffering agent]]s that reversibly bind hydrogen ions and impede any change in pH exist. [[Extracellular]] buffers include [[bicarbonate]] and [[ammonia]], whereas [[protein]]s and [[phosphate]] act as [[intracellular]] buffers. The [[bicarbonate buffering system]] is especially key, as [[carbon dioxide]] ({{CO2}}) can be shifted through [[carbonic acid]] ({{chem\|H\|2\|CO\|3}}) to hydrogen ions and [[bicarbonate]] ({{chem\|HCO\|3\|-}}) as shown below.<ref>{{cite book \|first1=Reginald H. \|last1=Garrett \|first2=Charles M \|last2=Grisham \|title=Biochemistry \|url=http://books.google.com/books?id=iGPsen3fSOIC&pg=PA43 \|year=2010 \|publisher=Cengage Learning \|isbn=978-0-495-10935-8 \|page=43}}</ref>
			:<center><math>\rm H_2O+CO_2 \leftrightarrow H_2CO_3 \leftrightarrow H^++HCO_3^-</math></center>

			Acid–base imbalances that overcome the buffer system can be compensated in the short term by changing the rate of [[Ventilation (physiology)\|ventilation]]. This alters the concentration of [[carbon dioxide]] in the blood, shifting the above reaction according to [[Le Chatelier's principle]], which in turn alters the pH. For instance, if the blood pH drops too low (''acidemia''), the body will compensate by increasing breathing<ref>{{MedlinePlusEncyclopedia\|000335\|Metabolic acidosis}}</ref> thereby expelling {{CO2}}, and shifting the above reaction to the left such that fewer hydrogen ions are free; thus the pH will rise back to normal. For ''alkalemia'', the opposite occurs.

			The [[kidneys]] are slower to compensate, but [[renal physiology]] has several powerful mechanisms to control pH by the excretion of excess acid or base. In response to acidosis, [[renal tubule\|tubular]] cells reabsorb more bicarbonate from the tubular fluid, [[collecting duct]] cells secrete more hydrogen and generate more bicarbonate, and [[ammoniagenesis]] leads to increased formation of the {{chem\|NH\|3}} buffer. In responses to alkalosis, the kidney may excrete more bicarbonate by decreasing hydrogen ion secretion from the tubular epithelial cells, and lowering rates of [[glutamine]] metabolism and ammonium excretion.

			==Imbalance==

			[[Acid–base imbalance]] occurs when a significant insult causes the blood pH to shift out of the normal range (7.35 to 7.45). In the [[fetus]], the normal range differs based on which [[umbilical vessel]] is sampled ([[umbilical vein]] pH is normally 7.25 to 7.45; [[umbilical artery]] pH is normally 7.18 to 7.38).<ref name="Yeomans">{{cite journal\|last=Yeomans\|first=ER\|coauthors=Hauth, JC; Gilstrap, LC III; Strickland DM\|title=Umbilical cord pH, PCO2, and bicarbonate following uncomplicated term vaginal deliveries (146 infants)\|journal=Am J Obstet Gynecol\|year=1985\|volume=151\|pages=798–800\|pmid=3919587}}</ref> An excess of acid in the blood is called [[acidemia]] and an excess of base is called [[alkalemia]]. The process that causes the imbalance is classified based on the [[etiology]] of the disturbance (respiratory or metabolic) and the direction of change in pH (acidosis or alkalosis). There are four basic processes: [[metabolic acidosis]], [[respiratory acidosis]], [[metabolic alkalosis]], and [[respiratory alkalosis]]. One or a combination may occur at any given time.

			==References==
			{{Reflist}}

			==External links==
			* [http://www.acidbase.org Stewart's original text at acidbase.org]
			* [http://www.anaesthesiamcq.com/AcidBaseBook/ABindex.php On-line text at AnaesthesiaMCQ.com]
			* [http://www2.kumc.edu/ki/physiology/course/nine/9_1.htm Overview at kumc.edu]
			* [http://www.acid-base.com/physiology.php Tutorial at acid-base.com]
			* [http://www.anaesthesiamcq.com/AcidBaseBook/ABindex.php Online acid–base physiology text]
			* [http://www.lakesidepress.com/pulmonary/ABG/MixedAB.htm Diagnoses at lakesidepress.com]
			* [http://www.nda.ox.ac.uk/wfsa/html/u16/u1602_01.htm Interpretation at nda.ox.ac.uk]
			{{Cardiopulmonary therapy}}
			{{Renal physiology}}
			{{Human homeostasis}}

			{{DEFAULTSORT:Acid-base homeostasis}}
			[[Category:Human homeostasis]]
			[[Category:Acid-base physiology]]
			[[Category:Acid-base disturbances]]
			[[Category:Equilibrium chemistry]]
			[[Category:Respiratory therapy]]

165.112.77.29: /* Mixing Based on Discrete Characteristics */ Deleted "or bipartite." The ability of e_ij to be asymmetric on ANY graph (including bipartite) only depends on whether it is directed.

2010-07-13T19:35:53Z

Mixing Based on Discrete Characteristics: Deleted "or bipartite." The ability of e_ij to be asymmetric on ANY graph (including bipartite) only depends on whether it is directed.

New page

The writer's title is Christy Brookins. For years he's been living in Alaska and he doesn't plan on altering it. One of the extremely best things in the world for him is performing ballet and he'll be beginning some thing else alongside with it. Office supervising is my occupation.<br><br>my web blog: real psychics [[http://www.skullrocker.com/blogs/post/10991 Read the Full Post]]

Mixing patterns - Revision history

en>Chris the speller: per WP:HYPHEN, sub-subsection 3, points 3,4,5, replaced: commonly- → commonly , currently- → currently using AWB

165.112.77.29: /* Mixing Based on Discrete Characteristics */ Deleted "or bipartite." The ability of e_ij to be asymmetric on ANY graph (including bipartite) only depends on whether it is directed.