Renal Anatomy study-question guide

1. Urinary system overview and functions

1. Name the four organs of the urinary system and the job of each. Recall
2. List the functions of the kidneys, including the two hormones they are tied to (erythropoietin and activated vitamin D) and what each does. Apply
3. The ureters move urine by peristalsis rather than gravity. Reason why that matters for a person lying down. Reason

2. Kidney location and orientation

1. Where do the kidneys sit? Give the body space and the vertebral levels. Recall
2. Which way does the hilum (concave side) face, and which kidney sits lower and why? Apply
3. Given that the kidneys are retroperitoneal, predict which surface faces the peritoneal cavity. Reason

3. External layers of the kidney

1. Name the three external layers of the kidney from superficial to deep. Recall
2. Give the tissue of the renal fascia, the perirenal fat capsule, and the renal capsule. Apply
3. What is nephroptosis, and how does loss of the fat capsule relate to it? Reason

4. Internal structure of the kidney

1. Contrast the renal cortex and renal medulla: name the components and the primary function of each. Recall
2. Name the structures that carry urine from the renal pyramids toward the ureter (papilla, minor and major calyces, renal pelvis). Apply
3. Why does the medulla, not the cortex, do the concentrating of urine? Reason from what sits in each region. Reason

5. Cortical and juxtamedullary zones

1. Where is the cortical zone versus the juxtamedullary zone, and roughly what percent of nephrons sits in each? Recall
2. Which zone has long loops of Henle that dive deep into the medulla, and which capillary network (vasa recta) serves them? Apply
3. Reason why long loops of Henle plus the vasa recta are required to make concentrated urine. Reason

6. The nephron and its two types

1. Define the nephron, give its location, and list its components in order. Recall
2. Contrast cortical and juxtamedullary nephrons by loop length, glomerulus position, and which capillary bed the efferent arteriole supplies. Apply
3. The two nephron types are named by location. Reason how their names predict their loop length. Reason

7. Renal corpuscle

1. Name the two parts of the renal corpuscle and give its location. Recall
2. Contrast the parietal and visceral layers of Bowman's capsule by tissue, and name the special cells of the visceral layer (podocytes) and the glomerulus (mesangial cells). Apply
3. Podocytes wrap the glomerular capillaries. Reason how their structure suits a filtration barrier. Reason

8. Proximal convoluted tubule

1. Where is the PCT located, and what epithelium forms its wall? Recall
2. Name the two apical and basal-lateral features (dense microvilli, infolded membranes, abundant mitochondria) and what each contributes to resorption. Apply
3. The PCT is packed with mitochondria and microvilli. Reason what that predicts about how active this segment is. Reason

9. Loop of Henle

1. Describe the shape of the loop of Henle and name its two limbs. Recall
2. Distinguish the thick and thin segments of the descending and ascending limbs. Apply
3. Reason why the loop's job is described as concentration and dilution of the filtrate depending on the segment. Reason

10. Distal convoluted tubule

1. Where is the DCT confined, and what epithelium forms it? Recall
2. Compare the DCT to the PCT in microvilli and resorptive activity. Apply
3. The DCT has few microvilli compared to the PCT. Reason what that tells you about its level of resorption. Reason

11. Collecting duct and renal papilla

1. Trace the path from the distal tubule through the collecting duct, papillary ducts, renal papilla, and into the minor calyces. Recall
2. At what point does filtrate officially become urine, and what epithelium lines the collecting duct? Apply
3. Contrast principal cells and intercalated cells of the collecting duct by what each regulates. Reason

12. Hilum of the kidney

1. Define the hilum and list the structures that pass through it. Recall
2. For the renal artery, renal vein, and ureter, state what each carries and to or from where. Apply
3. Reason why the renal vein carries both deoxygenated and filtered blood away from the kidney. Reason

13. Blood supply to and through the kidney

1. The kidneys receive roughly what fraction of resting cardiac output? Recall
2. List the arterial path in order from the renal artery to the glomerulus, then out through the efferent arteriole to the peritubular capillaries or vasa recta and back to the renal vein. Apply
3. A glomerulus sits between two arterioles rather than an arteriole and a venule. Reason why that arrangement is unusual and what it allows. Reason

14. Juxtaglomerular apparatus

1. What are juxtaglomerular cells (modified smooth muscle), where are they, and what do they synthesize, store, and secrete? Recall
2. Name the triggers for renin release (low blood pressure, low sodium, sympathetic activation) and the system the JGA regulates (RAAS). Apply
3. The JG cells act as mechanoreceptors in the afferent arteriole. Reason how that lets them sense blood pressure directly. Reason

15. Ureters

1. Give the function of the ureters and the tissue layers of their wall from lumen outward (transitional epithelium/urothelium, lamina propria, muscularis, adventitia). Recall
2. What moves urine through the ureters, and which layer produces that movement? Apply
3. Reason why transitional epithelium (urothelium) is the right lining for a tube that must stretch. Reason

16. Urinary bladder

1. Give the function of the bladder, its average capacity, the volume at which the urge to void is felt, and the muscle in its wall (detrusor). Recall
2. What epithelium lines the bladder, and where does the bladder sit in males versus females? Apply
3. Reason how the detrusor muscle and transitional epithelium together let the bladder fill without a big rise in pressure. Reason

17. Urethra and gender differences

1. Name the three regions of the male urethra in order, and give its approximate length. Recall
2. Contrast the male and female urethra by length and by dual versus single function. Apply
3. Reason how the length difference relates to differing infection risk between the sexes. Reason

18. Micturition: retention and expulsion

1. During the filling phase, what is the detrusor doing and what are the internal and external urethral sphincters doing? Recall
2. During emptying, which division of the autonomic nervous system contracts the detrusor and relaxes the internal sphincter, and which sphincter is under voluntary control? Apply
3. Stretch receptors in the bladder wall signal the brain as it fills. Reason how that closes the loop between a full bladder and the urge to void. Reason

19. Continence and incontinence

1. Contrast the internal and external urethral sphincters by control (involuntary vs voluntary), muscle type, and location. Recall
2. Define urge, stress, and overflow incontinence, and give a cause of each. Apply
3. Reason why weakened pelvic floor muscles produce stress incontinence but not urge incontinence. Reason

Stuck on one? Open the lecture slides or the concept videos, find the structure, and trace it, then come back and answer from memory.