Chapter 27, part 2SECTION 27-5 Acid-base BalanceThe importance of pH controlTypes of acids in the bodyCommon AcidsMechanisms of pH controlSlide 7Figure 27.6 The Basic Relationship between PCO2 and Plasma pHFigure 27.7 Buffer Systems in Body FluidsProtein buffer systemFigure 27.8 Amino Acid BuffersCarbonic Acid-Bicarbonate Buffering SystemFigure 27.9 The Carbonic Acid-Bicarbonate Buffer SystemMaintenance of acid-base balanceFigure 27.10 Kidney tubules and pH RegulationSlide 16SECTION 27-6 Disturbances of Acid-base BalanceAcid-base balance maintained byFigure 27.11 The Central Role of the Carbonic Acid-Bicarbonate Buffer System in the Regulation of Plasma pHSlide 20Acid-Base DisordersRespiratory acidosisFigure 27.12 Respiratory Acid-Base RegulationSlide 24Respiratory alkalosisMetabolic acidosisFigure 27.13 The Response to Metabolic AcidosisMetabolic alkalosisFigure 27.14 Metabolic AlkalosisDetection of acidosis and alkalosisFigure 27.15 A Diagnostic Chart for Acid-Base DisordersSECTION 27-7 Aging and Fluid, Electrolyte, and Acid-base BalanceChanges with age includeYou should now be familiar with:Slide 35Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Fundamentals of Anatomy & PhysiologySIXTH EDITIONFrederic H. MartiniPowerPoint® Lecture Slide Presentation prepared by Dr. Kathleen A. Ireland, Biology Instructor, Seabury Hall, Maui, HawaiiChapter 27, part 2Fluid, Electrolyte, and Acid-Base BalanceCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsSECTION 27-5 Acid-base BalanceCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•The pH of the ECF remains between 7.35 and 7.45•If plasma levels fall below 7.35 (acidemia), acidosis results•If plasma levels rise above 7.45 (alkalemia), alkalosis results•Alteration outside these boundaries affects all body systems •Can result in coma, cardiac failure, and circulatory collapseThe importance of pH controlCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Volatile acid •Can leave solution and enter the atmosphere (e.g. carbonic acid)•Fixed acids•Acids that do not leave solution (e.g. sulfuric and phosphoric acids)•Organic acids•Participants in or by-products of aerobic metabolism Types of acids in the bodyCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Carbonic acid is most important factor affecting pH of ECF•CO2 reacts with water to form carbonic acid•Inverse relationship between pH and concentration of CO2•Sulfuric acid and phosphoric acid •Generated during catabolism of amino acids•Organic acids•Metabolic byproducts such as lactic acid, ketone bodiesCommon AcidsCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Buffer system consists of a weak acid and its anion•Three major buffering systems:•Protein buffer system•Amino acid •Hemoglobin buffer system •H+ are buffered by hemoglobin•Carbonic acid-bicarbonate •Buffers changes caused by organic and fixed acidsMechanisms of pH controlCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Three major buffering systems (continued):•Minor buffering system•Phosphate•Buffer pH in the ICFMechanisms of pH controlCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.6Figure 27.6 The Basic Relationship between PCO2 and Plasma pHAnimation: Relationship Between PCO2 and Plasma pHPLAYCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.7 Buffer Systems in Body FluidsFigure 27.7Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•If pH climbs, the carboxyl group of amino acid acts as a weak acid•If the pH drops, the amino group acts as a weak base•Hemoglobin buffer system•Prevents pH changes when PCO2 is rising or fallingProtein buffer systemCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.8 Amino Acid BuffersFigure 27.8Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Carbonic acid-bicarbonate buffer system•CO2 + H2O  H2CO3  H+ + CO3–•Has the following limitations:•Cannot protect the ECF from pH changes due to increased or depressed CO2 levels•Only functions when respiratory system and control centers are working normally•It is limited by availability of bicarbonate ions (bicarbonate reserve)Carbonic Acid-Bicarbonate Buffering SystemCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.9a, bFigure 27.9 The Carbonic Acid-Bicarbonate Buffer SystemCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Lungs help regulate pH through carbonic acid - bicarbonate buffer system•Changing respiratory rates changes PCO2•Respiratory compensation•Kidneys help regulate pH through renal compensationMaintenance of acid-base balanceCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.10 Kidney tubules and pH RegulationFigure 27.10a, bCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.10 Kidney tubules and pH RegulationFigure 27.10cCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsSECTION 27-6 Disturbances of Acid-base BalanceCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Buffer systems•Respiration•Renal function•Maintain tight control within range 7.35 – 7.45Acid-base balance maintained byCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.11aFigure 27.11 The Central Role of the Carbonic Acid-Bicarbonate Buffer System in the Regulation of Plasma pHCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.11bFigure 27.11 The Central Role of the Carbonic Acid-Bicarbonate Buffer System in the Regulation of Plasma pHCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Respiratory acid base disorders•Result when abnormal respiratory function causes rise or fall in CO2 in ECF•Metabolic acid-base disorders•Generation of organic or fixed acids•Anything affecting concentration of bicarbonate ions in ECF Acid-Base DisordersCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Results from excessive levels of CO2 in body fluidsRespiratory acidosisCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 27.12