2. Acid-Base Interactive Tutorial.

3. Acid-Base Pretest:  What is the normal range for arterial blood pH? 7.38 – 7.46 7.40 – 7.52 7.35 – 7.45

4. Correct!  This is the correct parameters for arterial blood pH with the extracellular fluid in the middle at 7.40… well done! Next QuestionPrevious Question

5. Acid-Base Pretest:  What 2 extracellular substances work together to regulate pH? Sodium bicarbonate & carbonic acid Carbonic acid & bicarbonate Acetic acid & carbonic acid

6. Correct!  Right on! Carbonic acid and bicarbonate are the two primary extracellular regulators of pH. pH is also further regulated by electrolyte composition within the intra & extracellular compartments. Next QuestionPrevious Question

7. Acid-Base Pretest:  Characterize an acid & a base based on the choices below. Acids release hydrogen (H + ) ions & bases accept H + ions. Acids accept H + ions & bases release H + ions Both acids & bases can release & accept H + ions

8. Correct!  Acids are molecules that have the ability to release H + ions & bases are molecules that have the ability to accept or bind with H + ions. Next QuestionPrevious Question

9. Acid-Base Pretest:  Buffering is a normal body mechanism that occurs rapidly in response to acid- base disturbances in order to prevent changes in what? HCO 3 - H 2 CO 3 H+H+

10. Correct!  Excellent! H + ion concentration is most important to regulate in order to prevent acid-base balance disturbances. Next QuestionPrevious Question

11. Acid-Base Pretest:  What are the two systems in the body that work to regulate pH in acid-base balance & which one works fastest? The Respiratory & Renal systems Renal The Respiratory & Renal systems Respiratory The Renal & GI systems Renal

12. Correct!  Great work! Both the respiratory & renal systems work to regulate pH in acid- base imbalance; the respiratory system works in a matter of minutes & is maximal within 12-24 hours while the renal (kidneys) system continues to function for days to restore pH within normal limits (WNL). End PretestPrevious Question

13. Acids and Bases can be strong or weak:  A strong acid or base is one that dissociates completely in a solution dissociates - HCl, NaOH, and H 2 SO 4HCl, NaOH, and H 2 SO 4  A weak acid or base is one that dissociates partially in a solution -H 2 CO 3, C 3 H 6 O 3, and CH 2 OH 2 CO 3, C 3 H 6 O 3, and CH 2 O

15. Protein Buffer Systems:  Largest buffer system in the body  Amphoteric: can function as acids or bases  Contain several ionizable groups able to bind or release H +  Largely located in cells; H + & CO 2 diffuse across cell membranes for buffering by Albumin & plasma globulins Albumin & plasma globulins Previous Slide

16. Bicarbonate Buffer System:  Uses NaHCO 3 as its weak base & H 2 CO 3 as its weak acidNaHCO 3H 2 CO 3  The HCO 3 - /CO 2 buffer system can readily add or remove components from the body  An ample supply of CO 2 provided via metabolism, replaces H 2 CO 3 lost when excess base is added  In turn, the kidneys conserve or form new HCO 3 - in the presence of excess acid & excrete HCO 3 - in the presence of excess base Previous Slide

17. Quick Review: Click the Boxes A donator of H + ionsAn acceptor of H + w/ pH 7.0 Regulated by EC Controlled by EC H 2 CO 3 & HCO 3 - & IC buffer systems Eliminates CO 2 Conserves HCO 3 - Eliminates H + ions An Acid is:A Base is: pH is: Respiratory System: pH is: Renal System:

18. The Phosphate Buffer system:  Uses HPO 42 - and H 2 PO 4 - present in tubular filtrateHPO 42 - and H 2 PO 4 -  Both become concentrated in the fluid due to relatively poor absorption & reabsorption of H 2 O from tubular fluid  H + combines w/ HPO 42 - to form H 2 PO 4 - giving the kidneys the ability to increase secretion of H + ions  When H + ions in the bloodstream decrease, pH increases & vice versa  Subsequently hydrogen phosphate either accepts or releases H + ions to maintain pH within the bloodstream Previous Slide

19. The Ammonia Buffer System:  This buffer system is the more complex of the two  The generation of HCO 3 - & excretion of H + by this system occurs in 3 steps: 1) synthesis of NH 4 + from glutamine, an amino acid in the proximal tubule, thick ascending loop of Henle & distal tubulesNH 4 +proximal tubulethick ascending loop of Henle distal tubules 2) recycling & reabsorption of NH 3 in the kidney’s medulla, &NH 3 3) buffering of H + ions by NH 3 in the collecting tubules. Previous Slide

20. Acid-Base Balance Review test:  The kidneys regulate pH by excreting HCO 3 - and retaining or regenerating H + TRUE FALSE

21. Incorrect  Actually the kidneys work to regulate pH through the regeneration or reabsorption of HCO 3 - & excretion of H + Next QuestionPrevious Question

22. Correct!  You’re absolutely right! The kidneys actually do the opposite in order to regulate pH. Nicely done. Next QuestionPrevious Question

23. Acid-Base Review test:  H 2 CO 3 splits into HCO 3 - & H + & it is the H + that stimulates either an increase or decrease in the rate & depth of respirations. TRUE FALSE

24. Correct!  You got it! This is because H +, along with CO 2 in the blood stream, act directly on respiratory centers in the brain. Next QuestionPrevious Question

25. Incorrect  The correct answer is TRUE. Please review the Respiratory Control Mechanisms slide as needed. Next QuestionPrevious Question

26. Acid-Base Review test:  Plasma concentration of HCO 3 - is controlled by the kidneys through reabsorption/regeneration of HCO 3 -, or elimination of buffered H + via the tubular systems. TRUE FALSE

27. Correct!  Yes! Reabsorption of filtered HCO 3 - or generation of new HCO 3 - & or H + ion elimination via phosphate & ammonia buffer systems help the kidneys regulate plasma concentrations of HCO 3 -. Next QuestionPrevious Question

28. Incorrect  Please review Mechanisms of Acid-Base balance if needed. Next QuestionPrevious Question

29. Acid-Base Review test:  The ratio of H + to HCO 3 - determines pH. TRUE FALSE

30. Incorrect  The answer is false. It’s the ratio of HCO 3 - to volatile H 2 CO 3 that determines pH. Next QuestionPrevious Question

31. Correct!  You’re right, the answer is false. REMEMBER: concentrations of volatile H 2 CO 3 are regulated by changing the rate & depth of respirations. Next QuestionPrevious Question

32. Acid-Base Review test:  Secreted H + couples with filtered HCO 3 - & CO 2 & H 2 O result. TRUE FALSE

33. Correct!  Well done! If you look back at the H + Elimination & HCO 3 - Conservation slide, this is part of the Na + /H + transport system. End Post testPrevious Question

34. Incorrect  Sorry, but the correct answer is true. End Post testPrevious Question