2. KIDNEYS KIDNEYS KIDNEYS KIDNEYS KIDNEYS KIDNEYS KIDNEYS KIDNEYS

4. What is urine? Mostly water Solutes: urea (from breakdown of protein), uric acid (from breakdown of nucleic acids), creatinine (from breakdown of creatine phosphate in muscle fibers), sodium, potassium, ammonia, NOT FOUND: glucose, proteins, rbc, hemoglobin, wbc, and bile

5. ANATOMICAL PARTS REGIONS: Renal cortex: superficial Renal medulla: inner region containing renal pyramids: Apex (papilla) face the hilus (kidney indentation) renal column: between pyramids

6. More parts minor calyx; major calyces – collect urine from pyramid Renal pelvis – collect urine from calyces Nephrons – filter urine from blood; microscopic URETER

8. URINE FORMATION Occurs in nephrons: mostly in renal cortex Leaves through collecting ducts

10. 1. Glomerular filtration Water and small solutes from blood Glomerular capsule Due to high bp

12. 2. Tubular reabsorption Returns useful nutrients to blood Ex: water, glucose, sodium, calcium

13. 3. Tubular secretion Brings some substances into the urine that are not already there. Ex: ammonium ions, hydrogen, some drugs

14. blood supply

19. 1. What is the difference between the renal cortex and the renal medulla?

20. 2. What part of the kidney is the hilus?

21. 3. What part of the kidney collects urine from a medullary pyramid?

22. 4. What is the function of a nephron?

23. 5. Which structure of the urinary system leaves the kidneys with urine?