PowerPoint ® Lecture Slides prepared by Leslie Hendon, University of Alabama, Birmingham HUMAN ANATOMY fifth edition MARIEB | MALLATT | WILHELM 23 Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings The Urinary System PART 1

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings The Urinary System  Important functions of the kidneys  Maintain the chemical consistency of blood  Filter many liters of fluid from blood  Send toxins, metabolic wastes, and excess water out of the body  Main waste products  Urea  Uric acid  Creatinine

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Organs of the Urinary System  Kidneys  Ureters  Urinary bladder  Urethra Figure 23.1a

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Location and External Anatomy of Kidneys  Located retroperitoneally  Lateral to T 12 –L 3 vertebrae  Average kidney  12 cm tall, 6 cm wide, 3 cm thick  Hilus  On concave surface  Vessels and nerves enter and exit  Renal capsule surrounds the kidney

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Relationship of the Kidneys to Vertebra and Ribs Figure 23.1b

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Position of the Kidneys with in the Posterior Abdominal Wall Figure 23.2a

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Internal Gross Anatomy of the Kidneys  Frontal section through the kidney  Renal cortex  Renal pyramids  Renal pelvis  Major calicies  Minor calicies  Gross vasculature  Renal arteries  Branch into segmental arteries

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Summary of Blood Vessels Supplying the Kidney Figure 23.3c

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Internal Gross Anatomy of the Kidneys  Nerve supply – renal plexus  A network of autonomic fibers  An offshoot of the celiac plexus

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Internal Anatomy of the Kidneys Figure 23.3b

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Microscopic Anatomy of the Kidneys  Uriniferous tubules  Composed of  Nephron  Renal corpuscle plus renal tubules  Collecting duct  Involved in concentrating urine PLAY Nephron

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Mechanisms of Urine Production  Filtration  Filtrate of blood leaves kidney capillaries  Reabsorption  Most nutrients, water, and essential ions reclaimed  Secretion  Active process of removing undesirable molecules

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Basic Kidney Functions Figure 23.4