1. Essentials of Anatomy and Physiology Fifth edition Seeley, Stephens and Tate Slide 2.1 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Chapter 18: Urinary System

2. General Information Slide 15.1a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Waste products of metabolism are toxic (CO 2, ammonia, etc.)  Removal from tissues:  by blood and lymph  Removal from blood by:  Respiratory system  Urinary system

3. Functions of the Urinary System Slide 15.1a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Elimination of waste products  Nitrogenous wastes  Toxins  Drugs

4. Functions of the Urinary System Slide 15.1b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Regulate homeostasis  Water balance  Electrolytes  Acid-base balance in the blood  Blood pressure  Red blood cell production

5. Organs of the Urinary system Slide 15.2 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Kidneys  Ureters  Urinary bladder  Urethra Figure 15.1a

6. Location of the Kidneys Slide 15.3 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Retroperitoneally  Lateral to vertebral column  The right kidney is slightly lower than the left  Atop each kidney is an adrenal gland

7. Organs of the Urinary system Slide 15.2 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Kidneys Figure 15.1a

8. Coverings of the Kidneys Slide 15.4 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Renal capsule  Surrounds each kidney  Adipose capsule  Surrounds the kidneys  Provides protection to the kidneys  Helps hold kidneys in place

9. Regions of the Kidney Slide 15.5 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Renal cortex: outer region  Renal medulla: pyramids and columns  Renal pelvis: collecting system Figure 15.2b

10. Kidney Structures Slide 15.6 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Medullary pyramids – triangular regions of tissue  Renal columns – cortical material between pyramids  Calyces (sing. Calyx)  cup-shaped structures  collect urine

11. Structures involved in Urine Formation Slide 15.6 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Vascular Components  Afferent arteriole  Glomerulus  Efferent arteriole  Peritubular capillaries  Tubular Components  Bowman’s capsule  Proximal convoluted tubule  Loop of Henle  Distal convoluted tubule

12. Blood Flow in/to the Kidneys Slide 15.7 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 15.2c Is extensive!!!

13. Nephrons Slide 15.8 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  The structural and functional units of the kidneys  Responsible for forming urine  Components of the nephrons  Renal corpuscle  Glomerulus and Bowman’s capsule  Renal tubules

14. Glomerulus (“a ball of yarn”) Slide 15.9a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  A specialized capillary bed  Attached to arterioles on both sides  Wide afferent arteriole  Narrow efferent arteriole Figure 15.3c

15. Glomerulus Slide 15.9b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Covered by glomerular capsule  first part of the renal tubule  AKA Bowman’s capsule Figure 15.3c

16. Renal Tubule Slide 15.10 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Bowman’s capsule  Proximal convoluted tubule  (PCT) Figure 15.3b

17. Renal Tubule Slide 15.10 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Loop of Henle  Distal convoluted tubule  DCT Figure 15.3b

18. Peritubular Capillaries Slide 15.12 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Arise from efferent arteriole  Attached to a venule distally  Surround renal tubule  Reabsorb substances from tubules into blood

19. Renal Tubule Slide 15.10 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Peritubular capillaries Figure 15.3b

20. Urine Formation Processes Slide 15.13 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Filtration  Reabsorption  Secretion Figure 15.4

21. Filtration Slide 15.14 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Nonselective passive process  Depends on hydrostatic pressure  Stops if B.P. falls too low  Water and some solutes (no proteins)  forced through capillary walls  Taken out of blood

22. Filtration Slide 15.14 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Blood cells cannot pass  Filtrate is collected in the glomerular capsule  This will become urine  Leaves capsule through the renal tubule  Alterations to filtrate occur in tubule

23. Reabsorption Slide 15.15 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Moving reusable material back into the blood  The peritubular capillaries reabsorb several materials  Some water  Glucose  Amino acids  Ions

24. Reabsorption, con’t… Slide 15.15 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Some is passive, most is active  65% of reabsorption occurs in the PCT  Glucose, Na +, Ca ++, Cl -, HCO 3 -  Water (by osmosis)  Amino acids (by pinocytosis)

25. Reabsorption, con’t… Slide 15.15 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Loop of Henle  15% more filtrate reabsorbed  Descending limb:  Water, by osmosis  Ascending limb:  Cl - by active transport  Na + by diffusion

26. Materials Not Reabsorbed Slide 15.16 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Nitrogenous waste products  Urea  Uric acid  Creatinine  Excess water

27. Secretion: Reabsorption in Reverse Slide 15.17 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Some materials move from peritubular capillaries into renal tubules  Hydrogen and potassium ions  Creatinine  Most secretion occurs in DCT

28. Secretion: Reabsorption in Reverse Slide 15.17 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  What’s left?? Urine!  Moving urine out of kidneys: tubules   collecting duct  minor calyces  major calyces  renal pelvis  ureter

29. Formation of Urine Slide 15.18 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 15.5

30. Normal components of Urine Slide 15.19 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Straw colored (pale yellow)  Sterile  Slightly aromatic  Normal pH of around 6  Specific gravity of 1.001 to 1.035

31. Normal volume of Urine Slide 15.19 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  0.6 – 2.5 liters/day. Depends on:  Adequate B.P.  Fluid intake  Temperature, humidity  Activity levels  <30cc/hour output = kidney failure  Average is 115-125 ml/hr

32. Abnormal components of Urine Slide 15.19 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Glucose  Ketones  Hemoglobin/blood cells  Proteins  pH 8

33. Ureters Slide 15.20 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Tubes attaching kidney to urinary bladder  Continuous with the renal pelvis  Enter the posterior aspect of the bladder  Retroperitoneal  Peristalsis, gravity move urine