Lecture 19: Urinary System Anatomy & Physiology PDF

Chapter 25 Urinary System...

Chapter 25 Urinary System B305 – Human Anatomy Dr. Preston ©2020 McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior written consent of McGraw-Hill Education.  Functions of the Urinary System o Storage of urine o Expulsion of urine (metabolic waste) o Regulation of blood volume (blood pressure) o Regulation of erythrocyte (erythropoietin [EPO]) o Regulation of ion levels o Regulation of acid-base balance © McGraw Hill 2  Anatomy of the Urinary System Kidneys (2) – retroperitoneal Bladder – pelvic cavity Ureters (2) – retroperitoneal Urethra © McGraw Hill 3  Anatomy of the Kidney Size: 5 inches long (12 cm) 3 inches wide (8 cm) 2 inches thick (5 cm) Weight: 10 to 12 ounces (280 to 340 grams) © McGraw Hill 4  Anatomy of the Kidney Kidneys are retroperitoneal Location: Left kidney is at the level of T12 – L4 Right kidney is ~ 2 cm lower 12th rib crosses the middle of left kidney © McGraw Hill 5  Anatomy of the Kidney © McGraw Hill 6  Anatomy of the Kidney © McGraw Hill 7  Gross Anatomy of the Kidney Hilum: Vessels, nerves, and ureter connect The hilum is continuous with the renal sinus Renal Hilum © McGraw Hill 8  The Kidney Renal sinus: Renal Sinus o Cavity containing vessels, nerves, and urine-collecting structures Renal parenchyma: o Glandular tissue - forms urine o C-shaped in frontal section Renal Parenchyma o Encircles renal sinus © McGraw Hill 9  Kidney – Renal Parenchyma Renal parenchyma Zones: Renal Pyramid o Outer renal cortex o Inner renal medulla Renal Cortex Renal columns o Extensions of cortex Renal pyramids o Renal medulla region o ~ 8 pyramids/kidney Renal Column o Wide base facing cortex and renal papilla (point) facing sinus © McGraw Hill 10  Kidney – Renal Parenchyma Lobe of kidney: a Renal Lobe of pyramid and its cortex Pyramid Kidney Minor calyx: next to Renal Cortex renal papilla; collects urine Major calyx: union of 2 or 3 minor calyces Renal pelvis: union of major calyces Renal Column © McGraw Hill 11  Renal Circulation Kidneys receive 21% of cardiac output (renal fraction) © McGraw Hill 12  Renal Circulation © McGraw Hill 13  The Nephron The nephron is the functional filtration unit of the kidney Each kidney has about 1.2 million nephrons Two main parts: o Renal corpuscle: filtering the blood plasma o Renal tubule: converts filtrate into urine © McGraw Hill 14  Types of Nephrons Cortical nephron Juxtamedullary nephrons: Juxtamedullary o 15% of all nephrons nephron o Near corticomedullary junction Cortical nephrons: o 85% of all nephrons o Peritubular capillaries wrap around them © McGraw Hill 15  Causes of Chronic Kidney Disease © McGraw Hill 16  Causes of Chronic Kidney Disease © McGraw Hill 17  Gross Anatomy of the Urinary Tract © McGraw Hill 18  Urinary Tract Components: Ureters Urinary bladder Urethra © McGraw Hill 19  The Ureters o Retroperitoneal, muscular tubes (~ 25 cm) o From hilum of kidney to bladder (posterolateral wall) o Flap of mucosa at entrance of each ureter acts as a valve into bladder Left Kidney Ureters Bladder © McGraw Hill Anatomy & Physiology Revealved 4.0 /McGraw-Hill Education 20  The Urinary Bladder Muscular sac located on floor of the pelvic cavity Retroperitoneal and posterior to pubic symphysis Trigone—triangular area on bladder floor, marked by openings of ureters and urethra © McGraw Hill 21  CT scan of Kidneys, Ureters and Bladder (KUB) https://youtu.be/Bzi1IPQx3Js?si=aTUkyyQHOWhGqI9K © McGraw Hill 22  End of Main Content Because learning changes everything. ® www.mheducation.com © 2021 McGraw Hill. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior written consent of McGraw Hill.