The Urinary System Human Anatomy & Physiology Miss Tavitian

What is the Urinary System? O Also known as the Renal System O Renal : of or involving kidney(s) O System that maintains appropriate fluid volume, electrolyte balance, pH of the blood

Main Players of the Urinary System O Kidneys O Ureters O Bladder O Urethra

Kidneys: Primary Organs of Excretion -Each day filter quarts of blood to produce 1-2 quarts of urine -Prevent buildup of waste and extra fluid -Keep electrolyte levels stable (Na+, K+, Phosphate)

Excretion vs. Defecation Excretion Defecation O Metabolic waste products once used in the body O Metabolism: the sum of all chemical reactions taking place in living organism O Releasing feces O Products that make up feces were never used in the body

Kidney’s continued… -Produce hormones that help: Regulate blood pressure [enzyme renin released when kidney blood supply low] make red blood cells [Erythropoietin] Keep bones strong [Calcitriol]

Hormones: Signaling Molecules Exocrine System Endocrine System O Hormones secreted by glands with ducts O Ducts are passage ways for the signaling molecules to travel O Hormones secreted by ductless glands O Hormones travel through the blood to reach target tissue

With the kidney’s release of renin: eventually lead to body reabsorb Na+ which leads to more fluid retention

As Area decreases, Pressure increases Aldosterone from the Adrenal Cortex helps blood vessels constrict which helps increase blood pressure

As mentioned, Kidneys Excrete Metabolic Wastes O liver breaks down Amino Acids  Ammonia is released. O Ammonia is too toxic for body, combines with CO2 to make Urea which then gets excreted in the urine

Kidney’s also excrete Creatine O Muscles use ATP for Energy and as a result produce ADP O Muscles constantly need ATP so will turn to Creatine Phosphate to go from ADP  ATP

Kidney’s also excrete Uric Acid O Uric Acid comes from body breaking down some nucleotides O Can dissolve in blood O Too much uric acid  hyperuricemia O Eventually crystals can form and lead to gout

Interesting fact Birds release poop and pee at the same time The white is the uric acid, brown is poop

Gout

Gout: foods to avoid O Foods to limit (very high in purines): O Organ meats, such as liver, kidneys, sweetbreads, and brainsliverkidneys O Meats, including bacon, beef, pork, and lamb O Game meats O Any other meats in large amounts O Anchovies, sardines, herring, mackerel, and scallops O Gravy O Beer

Parts of Kidney O Renal Cortex  outer edge O Renal medulla  middle portion O Renal Pelvis  basin where urine first enters

 Blood with Waste enters through Renal Artery  Clean blood exits and returns to heart through Renal Vein

Functional Unit of Kidney= Nephron O Each Kidney has 1 million Nephrons