Module P - Urinary System

Learning outcomes for this module as of Fall 2019:

Please note: Those headings with associated teaching tips are underlined, clickable links. However, while this identifies which topics have associated teaching tips, the actual list of teaching tips you click through to include all teaching tips for this module, not only the ones for one particular topic in this module.

Topic from HAPS Guidelines (in bold font)

Learning Outcomes (indented, regular font)^[1]

1. General functions of the urinary system

1. Describe the major functions of the urinary system and which organs are responsible for those functions.

2. Gross and microscopic anatomy of the kidney

1. Identify and describe the anatomic structure of the kidney, including its coverings.

2. Distinguish histologically between the renal cortex and the renal medulla.

3. Trace the path of blood flow through the kidney, from the renal artery to the renal vein.

4. Identify and describe the structure of a typical nephron, including the renal corpuscle (i.e.,glomerular [Bowman’s] capsule, glomerulus) and renal tubule (i.e., proximal convoluted tubule, nephron loop [loop of Henle], distal convoluted tubule).

5. Identify and describe the vascular elements associated with the nephron (i.e., afferent and efferent arterioles, glomerulus, peritubular capillaries, vasa recta).

6. Compare and contrast the anatomic structure of the cortical nephrons and juxtamedullary nephrons.

7. Trace the flow of filtrate from the renal corpuscle through the collecting duct.

8. Identify the location, structures and cells of the juxtaglomerular apparatus (JGA) and discuss its significance.

3. Gross and microscopic anatomy of the urinary tract (i.e., ureters, urinary bladder, urethra)

1. Identify and describe the gross anatomy and location of the ureters, urinary bladder, and urethra.

2. Identify and describe the microscopic anatomy of the ureters, urinary bladder, and urethra.

3. Compare and contrast the anatomy of the male urethra versus the female urethra.

4. Compare and contrast the locations, innervation and functions of the internal urethral sphincter and external urethral sphincter.

5. Trace the path of urine from the collecting duct of the kidney to the external urethral orifice.

4. Functional process of urine formation, including filtration, reabsorption, and secretion

1. Describe the three processes that take place in the nephron (i.e., filtration, reabsorption, and secretion) and explain how the integration of these three processes determines the volume and composition of urine.

2. Compare and contrast blood plasma, glomerular filtrate, and urine.

3. For any solute, explain how renal filtration, reabsorption, and secretion determine the excretion rate of that solute.

4. Describe the filtration structures that lie between the lumen of the glomerular capillaries and the capsular (Bowman) space.

5. Define glomerular filtration rate (GFR) and explain the role of blood pressure, capsule fluid pressure, and colloid osmotic (oncotic) pressure in determining GFR.

6. Describe factors that can change blood pressure, capsule fluid pressure, and colloid osmotic (oncotic) pressure and thereby change glomerular filtration rate (GFR).

7. Explain the role of the juxtaglomerular apparatus (JGA) in tubuloglomerular feedback.

8. Compare and contrast tubular reabsorption and secretion with respect to the direction of solute movement and the tubule segments in which each process occurs.

9. Describe specific mechanisms of transepithelial transport that occur in different parts of the nephron (e.g., active transport, osmosis, facilitated diffusion, electrochemical gradients, receptor-mediated endocytosis, transcytosis).

10. Give examples of each type of transepithelial transport, including the substance being transported, any membrane proteins involved, and the direction of movement across the tubule wall (e.g., water is reabsorbed from the collecting duct through aquaporin water channels).

11. For the important solutes of the body (e.g., Na+, K+, glucose, urea), describe how each segment of the nephron handles the solute and compare the filtration rate of the solute to its excretion rate (i.e., the net handling of the solute by the nephron).^[2]

12. Explain the difference between clearance of a solute and renal handling of a solute.

13. State the equation for clearance of a solute and explain how inulin and creatinine clearance are used to determine glomerular filtration rate (GFR).

14. Describe the percentage of filtrate that is reabsorbed in each segment of the nephron.

15. Trace the changes in filtrate osmolarity as it passes through the segments of the nephron.

16. Explain the role of the nephron loop (of Henle), its permeability to water, and the high osmolarity of the interstitial fluid in the renal medulla in the formation of dilute urine.^[3]

17. Describe the transport processes involved in eliminating drugs (e.g., penicillin), wastes, and foreign substances.

18. Describe the composition of normal urine.

5. Control of sodium, potassium, and water homeostasis

1. For the renin-angiotensin system (RAS), describe the factors that initiate renin release, the pathway from angiotensinogen to angiotensin II (ANGII), and the effects of ANGII on various tissues.

2. Describe the signals that cause release of aldosterone from the adrenal cortex and the effect of aldosterone on the nephron, including the tubule segment involved and the transport mechanisms that are altered by aldosterone.

3. Describe the effect of vasopressin (ADH, antidiuretic hormone) on the nephron and on the final concentration of urine.

4. Describe the factors that cause release of natriuretic peptide hormones, their sites of synthesis, and their effects on the nephron.

6. Additional endocrine activities of the kidney

1. Describe the role of the kidney in vitamin D activation.

2. Describe the role of the kidney in regulating erythropoiesis.

3. Describe the effect of parathyroid hormone (PTH) on renal handling of calcium and phosphate.

7. Micturition (urination)

1. Describe the micturition reflex and the role of the autonomic nervous system in the reflex.

2. Describe voluntary control of micturition.

8. Application of homeostatic mechanisms

1. Provide specific examples to demonstrate how urinary system processes help maintain solute and osmolarity homeostasis in the body.

9. Predictions related to disruption of homeostasis

1. Given a factor or situation (e.g., hyperglycemia), predict the changes that could occur in the urinary system and the consequences of those changes (i.e., given a cause, state a possible effect).

2. *Given a disruption in the structure or function of the urinary system (e.g., blood in the urine), predict the possible factors or situations that might have caused that disruption (i.e., given an effect, predict possible causes).

^[1] An asterisk (*) preceding a learning outcome designates it as an optional, advanced learning outcome. The HAPS A&P Comprehensive Exam does not address these optional learning outcomes.

^[2] We are choosing to include the renal handling of hydrogen ions and bicarbonate ions in the fluid/electrolyte discussion of acid/base balance (Module Q).

^[3] We are intentionally not including the details of the countercurrent mechanisms in these LOs because they are not essential for understanding renal function, and they are no longer taught in many medical physiology courses.