Exercise 9: Renal System Physiology Worksheet Glomerular Filtration Activity 1: Effect of Arteriole Diameter on Glomerular Filtration 1. Compare this data with your baseline data. How did increasing the afferent arteriole radius affect glomerular filtration rate? 2. Under these conditions, does the fluid flow through the nephron? 3. What is the glomerular filtration rate? 4. How does it compare to your baseline data, and why? 5. How did increasing the efferent radius affect glomerular filtration rate? 6. How did decreasing the efferent radius affect glomerular filtration rate? 7. Physiologically, what could be the cause of a change in afferent or efferent arteriole radius? Activity 2: Effect of Pressure on Glomerular Filtration 1. As pressure increased, what happened to the pressure in the glomerulus? 2. What happened to the glomerular filtration rate? 3. How did the urine volume change? 4. How could increased urine volume be viewed as being beneficial to the body? Activity 3: Combined Effects 1. What happened to the glomerular filtration rate and urine volume after you reduced the pressure? 2. How could you adjust the afferent or efferent radius to compensate for the effect of the reduced pressure on glomerular filtration rate and urine volume? Use the simulation to determine your answer. 3. What changes are seen in nephron function when the valve is closed? 4. Why were these changes seen? 5. Is the kidney functional when the glomerular filtration rate is zero? Explain your answer. 6. What is the major “ingredient” that needs to be removed from the blood? 7. Studies on aging have demonstrated that some nephrons may fail as we get older. Will this be a problem regarding urine formation? 8. If blood pressure went down – for example, as the result of blood loss – what changes would the kidney need to make to maintain its normal filtration rate? Simulating Urine Formation Activity 4: Effect of solute Gradient on Urine Concentration 1. How did the urine solute concentration change as the concentration gradient of the interstitial fluid increased? 2. What happened to the urine volume as the concentration gradient increased? Why? 3. By increasing the concentration gradient, what are you doing to the urine that is formed? 4. Predict what would happen to urine volume if you did not add ADH to the collecting duct. Activity 5: Reabsorption of Glucose 1. What happens to the glucose concentration as you add glucose carriers to the system? 2. At what point does the glucose concentration in the urine become zero? 3. What would you expect to find in the urine of a diabetic? Why? Activity 6: Effect of Hormones on Reabsorption 1. Which hormone has the greater effect on urine volume? Why? 2. How does the addition of aldosterone affect the concentration of potassium in the urine? 3. How does the addition of ADH affect the concentration of potassium in the urine? How does this compare to the effect of adding aldosterone, with respect to potassium concentration in the urine? 4. How does the addition of both hormones affect 1) urine concentration, 2) urine volume, and 3) potassium concentration? 5. If ADH were not used, how would the urine concentration vary? Explain your answer.
**bold**, to write a math equation use, for example,