1. 1 Urinary System

2. 2 Functions 1. 1. Excretion 2. 2. Elimination 3. 3. Homeostatic Regulation

3. Metabolic Wastes 1. Urea 2. Creatinine 3. Uric Acid 3

4. 4 Urinary System  Kidney regions: 1. Cortex  Direct filtration  cortical nephrons  juxtamedullary nephrons 2. Medulla  Reabsorption, Secretion 3. Pelvis excretion

5. 5 Overview of Urinary System Flow Flow 1. 1. Filtration 2. 2. Reabsorption 3. 3. Secretion

6. 6 Glomerular Filtration Filtration membrane Filtration membrane Net Filtration Pressure: Net Filtration Pressure: Glomerular hydrostatic pressure (HPg) (GBHB) Glomerular hydrostatic pressure (HPg) (GBHB) Colloid osmotic pressure (OPg) (BCOP) Colloid osmotic pressure (OPg) (BCOP) Capsular hydrostatic presure (HPg) (CHP) Capsular hydrostatic presure (HPg) (CHP) Glomerular Filtration Rate (GFR) Glomerular Filtration Rate (GFR)

7. 7 Tubular Reabsorption Reabsorption of organic nutrients Reabsorption of ions, water, and some molecules. Water reabsorption - osmotic changes due to active transport of sodium ions. Molecule reabsorption - secondary active transport initiated by ions. Types of Active Transport 1. 1. Co-transport 2. 2. Countertransport

8. Types of carrier mediated transport 1. Facilitated diffusion 2. Active Transport (secondary active) 1. Cotransport (symport) 2. Countertransport (antiport) 8

9. 9 Tubular Secretion Disposes of unwanted solutes Regulation of Urine Concentration and Volume countercurrent mechanism osmotic gradients Diuretics

10. 10 Maintaining Homeostasis Balances: Water/salt pH Blood pressure