physiology

1. Body Fluids and Transport

4. Key concepts involving water

7. BODY FLUIDS Distribution of Body Fluids ICF ECF 40% TBW 20% TBW P IS 60-kg man TBW = 0.6 x 60 kg = 36 L ICF = 0.4 x 60 kg = 24 L ECF = 12 L 3L 9L

8. Movement of molecule across cell membrane

12. Major characteristics of diffusion pathways Yes No Chemical specificity Ions Nonpolar Typical molecules using pathway Yes No Use of integral membrane protein Through protein Channels Through lipid Bilayer

25. Permeable to water, Not permeable to solutes Presence of a membrane Impermeable to solute That leads to the volume Changes associated with Osmosis.

29. Water diffuses in Water diffuses out

32. Transport, the big picture fig 4-15

33. Facilitated diffusion (properties) Passive, carrier mediated Examples: glucose into most cells (not luminal membrane of kidney or intestine), urea, some amino acids Kinetics: shows: passive shows: carrier mediated

34. Non-mediated vs. mediated transport fig 4-9

35. Primary active transport (Na + /K + ATPase pump) 3 Na + ’s out, 2 K + ’s in, 1 ATP hydrolyzed fig 4-11

36. Primary active transport (Na + /K + ATPase pump) 3 Na + ’s out, 2 K + ’s in, 1 ATP hydrolyzed fig 4-11

37. Primary active transport kinetics shows active transport shows carrier mediated

38. Effect of Na + /K + ATPase pump fig 4-12

39. Secondary active transport fig 4-13

40. Secondary active transport properties Active (energy from ion gradient, usually Na + ) Carrier mediated Can be cotransport (symport) or countertransport (antiport) Examples (many): Na + /amino acids, Na + /glucose (luminal membrane kidney, GI tract), *Na + /H + kidney, *Ca ++ /3Na + muscle, *Cl - /HCO 3 - red cell. (* = countertransport) Kinetics see primary active transport graphs

46. Mechanism of Na + Selective Reabsorption in Collecting Duct Figure 20-12: Aldosterone action in principal cells

49. Artial Natruretic Peptide: Regulates Na + & H 2 O Excretion Figure 20-15: Atrial natriuretic peptide

51. Potassium Balance: Critical for Excitable Heart & Nervous Tissues Figure 20-4: Osmolarity changes as fluid flows through the nephron

52. Potassium Balance: Critical for Excitable Heart & Nervous Tissues Figure 20-12: Aldosterone action in principal cells

54. Response to Dehydration & Osmolarity Imbalance

63. Acid/Base Homeostasis: Overview Figure 20-18: Hydrogen balance in the body

65. Kidney Hydrogen Ion Balancing: Proximal Tubule Figure 20-21: Proximal tubule secretion and reabsorption of filtered HCO 3 -

67. Kidney Hydrogen Ion Balancing: Collecting Duct Figure 20-22: Role of the intercalated cell in acidosis and alkalosis