Lab 19 The Urinary System Laboratory Objectives Identify and describe the micro- and macroscopic anatomy of the kidney. Track the blood flow in and out of the kidney. Compare blood, glomerular filtrate, and urine. Relate glomerular filtrate formation to the glomerular blood hydrostatic pressure, capsular hydrostatic pressure, and the blood colloidal osmotic pressure. Describe mechanisms that affect glomerular filtration rate. Compare the mechanisms of water reabsorption to solute reabsorption. Describe the function of the kidneys in controlling blood ph. Describe the interaction of the respiratory and renal systems in maintaining the normal blood ph. 1
Activity 1: Cadaver Video : The Urinary System Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > See > Cadaver Video: The Urinary System (5:16) 1. Which kidney is located more superiorly? Why? 2. What are the two primary vessels at the renal hilum? 3. What are the cortical extensions that separate the renal medulla into the renal pyramids? 4. Two or more major calyces come together to form what? 5. The renal arteries branch directly off of the. The renal veins drain directly into the. 6. Compare the anatomical position of the bladder in males and females. 2
Activity 2: Renal Filtration Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > See > Animation: Renal Filtration 1. What three processes are responsible for urine formation? Briefly describe each of them. 2. What forms the glomerular membrane? 3. Compare blood and glomerular filtrate. 4. What is the source of glomerular blood hydrostatic pressure? How does it encourage the formation of glomerular filtrate? 5. How do the capsular hydrostatic and blood colloidal osmotic pressures oppose filtrate formation. 6. How do the above pressures determine the net-filtration pressure? 3
Activity 2: Renal Filtration (continued) Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > See > Animation: Renal Filtration 7. What is the consequence of a high glomerular filtration rate (GFR)? 8. What is consequence of the low GFR? 9. What happens to the GFR if the smooth muscle in the afferent arteriole contracts? 10. What group of cells detects increased ion concentration in the glomerular filtrate and releases vasoconstriction chemicals to smooth muscle of the afferent arteriole? 11. How does sympathetic stimulation decrease the GFR? 4
Activity 3: Renal Reabsorption and Secretion Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > See > Animation: Renal Reabsorption and Secretion 1. Why is most of the filtrate reabsorbed back into the blood? 2. What is the difference between paracellular and transcellular reabsorption? 3. Name the five (5) transport mechanisms associated with reabsorption. 4. How does the reabsorption of water (by osmosis) further increase the reabsorption of ions? 5. Why do chloride ions follow sodium ions? 5
Activity 3: Renal Reabsorption and Secretion (continued) Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > See > Animation: Renal Reabsorption and Secretion 6. What is reabsorbed in the ascending limb of the loop of Henle. 7. Parathyroid hormone increases reabsorption of what mineral from the distal convoluted tubule? 8. Reabsorption involved five transport mechanisms. How many are involved in secretion? 9. Where does the reabsorption of water have the greatest effect on final urine concentration? 6
Activity 4: Magic Renal Ride Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > Do > Interactive Exercise: Magic Renal Ride 1. What is unique about the renal blood flow versus other organs of the body? 2. Which arteries transport blood through the renal columns? 3. Compare the peritubular capillaries and the vasa recta. 7
Activity 5: Filtration Finale Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > Do > Interactive Exercise: Filtration Finale 1. What is the main physical property that determines whether or not a substance will be present in the glomerular filtrate? 2. What would have to change for large proteins to be present in the glomerular filtrate? 3. So, if a person has red cells in their urine, there must be a problem with their glomerular membrane, right? 8
Activity 6: Pick the Urinary Process Navigation: WileyPlus > Read, Study, and Practice > Chapter 26. The Urinary System > Do > Interactive Exercise: Pick the Urinary Process 1. What role do the glomerular capillaries play in reabsorption? 2. Where in the nephron does water reabsorption not take place? 3. Where are the majority of nutrients reabsorbed? 9
Activity 7: Phix the ph Navigation: Chapter 27. Fluid, Electrolyte, and Acid-Base Homeostasis > Do > Interactive Exercise: Phix the ph 1. What is the normal blood ph? 2. What is the chemical equation for the bicarb/carbonic acid buffering system? 3. Compare respiratory acidosis and alkalosis. 4. How can the respiratory system affect metabolic acidosis due to renal failure? 10