EXERCISE Anatomy of the Urinary System 43
EXERCISE Answers to Questions 43
QUICKCHECK 1.1 The hilus is a slit-like passageway in the kidney for blood vessels, nerves, and the ureter. 1.2 The renal pyramids are located in the medulla of the kidney. 1.3 The renal columns are located between the renal pyramids. 2.1 A nephron has two main regions: the renal corpuscle and the renal tubule. 2.2 The two kinds of nephrons are cortical and juxtamedullary nephrons. 3.1 The renal arteries branch from the abdominal aorta to supply blood to the kidneys. 3.2 The interlobar arteries are located in the renal columns and the cortical radiate arteries are located in the cortex. 4.1 The ureters join the lower portion of the urinary bladder at the posterior two openings of the trigone. 4.2 The trigone is the smooth triangular region between the ureteral and urethral openings. 5.1 Always wear safety glasses and disposable examination gloves while dissecting. 5.2 Sheep kidneys, scrap tissue, and gloves should be discarded in the biohazard box.
LABORATORY REPORT A. Definition 1. Renal papilla: small tip of a renal pyramid that extends into a minor calyx 2. Cortex: superficial layer of the kidney that contains many cortical nephrons 3. Bowman’s capsule: tubular structure that houses the glomerulus where bood is filtered 4. Loop of Henle: long U-shaped region of the nephron 5. Renal sinus: cavity of the kidney between the major calyces 6. Nephron: tubular structure where blood is filtered and urine is produced, each kidney has approximently 1 million nephrons 7. Efferent arteriole: arteriole that exists Bowman’s capsule and branches into peritubular capillaries 8. Hilus: slit-like passageway for blood vessels, nerves, and the ureter
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9. Ureter: duct that drains urine from the renal pelvis to the urinary bladder 10. Arcuate artery: artery that passes along the junction of the renal pyramids and the cortex 11. Renal capsule: fibrous tissue on the surface of the kidney that protects from infection and trauma 12. Renal column: area of cortical tissue extending between the renal pyramids
B. Short-Answer Questions 1. The renal corpuscle consists of the Bowman’s capsule and the glomerulus. 2. Cortical nephrons have renal corpuscles in the middle of the cortex. Juxtamedullary nephrons have renal corpuscles near the medulla and a long loop of Henle that extends deep into the medulla. 3. The urethra in males extends through the penis and functions to transport semen or urine. The urethra in females only transports urine and it terminates in the vestibule between the clitoris and vagina. 4. The internal urethral sphincter is located in the wall of the urinary bladder at the entrance into the urethra. The external urethral sphincter is located in the urogenital diaphragm, the muscular floor of the pelvis.
C. Labeling Figure 43.5 1. segmental artery 5. cortical radiate arteries 2. renal artery 6. interlobar veins 3. renal vein 7. arcuate veins 4. interlobar arteries 8. arcuate arteries
D. Analysis and Application 1. The layers of the renal corpuscle through which filtrate must pass to enter the capsular space are as follows: capillary endothelium - cellular wall of glomerulus lamina densa - basement membrane of the capillary filtration slits - grooves between the pedicels of podocytes 2. Trace a drop of blood through the kidney: abdominal aorta - renal artery - segmental artery - interlobar artery - arcuate artery - interlobular artery - afferent arteriole - glomerulus - efferent arteriole - peritubular and vasa recta capillaries - interlobular vein - arcuate vein - interlobar vein - renal vein - inferior vena cava. 3. Trace a drop of urine from the minor calyx to the urinary bladder: minor calyx - major calyx - renal pelvis - ureter - urinary bladder.
E. Clinical Challenge 1. Nephroptosis is a detachment of the kidney from the adipsoe capsule or the renal fascia. The floating kidney can droop and pinch the ureter closed. 2. The prostate gland is inferior to the urinary bladder. The prostate can 180 Instructor’s Manual for Laboratory Manual for Anatomy & Physiology, Fourth Edition
enlarge as the male ages and the swollen gland constricts the urethra and urinating can become difficult.