Kidneys & Urinary System - Biomedical Science PDF

Kidneys & Urinary System Biomedical Science Coralie Frances GDC Learning Outcomes 1.1.5 Describe relevant and appropriate dental, oral, craniofacial and general anatomy and explain their applica;on to pa;ent management 1.1.6 Describe relevant and appropriate physiology and explain its app...

Kidneys & Urinary System Biomedical Science Coralie Frances GDC Learning Outcomes 1.1.5 Describe relevant and appropriate dental, oral, craniofacial and general anatomy and explain their applica;on to pa;ent management 1.1.6 Describe relevant and appropriate physiology and explain its applica;on to pa;ent management Intended Learning Outcomes At the end of the session the student should be able to: Label diagrams of the macroscopic & microscopic anatomy of the urinary system & kidney Describe the func;on of the urinary system & kidney Explain blood Dow through the nephron Explain how the nephron Flters the blood Describe homeostasis of water balance & electrolytes Assess your knowledge pre lecture What is the func;on of the urinary system? Filter blood and remove remove waste products from the body. Look at the next slide What type of secDon is this? cross section Kidney. What does your kidney do? Filtering blood, balancing chemicals, regulating blood pressure, stimulating red blood cell production,Converting vitamin D into its active form , aiding thermoregulation. Can you name the structures? Renal capsule, cortex, medulla, nephron, glomerulus, renal papilla, Minor and major calyces, renal pelvis, adrenal glands, renal Hilum What is their purpose? To remove waste products from the blood and produce urine How did you do? Rate your knowledge on a score of 1-5 (1 least knowledge; 5 greatest knowledge) Con;nue with the PPT to refresh your knowledge then answer the same ques;ons again What are your scores now? Anatomy & Physiology Anatomy Physiology Watch these 3 videos hRps://www.youtube.com/playlist?list=PLzl4lgX_3RvcgRqo810pAcz9trinh0Irl The Urinary System Aorta Inferior vena cava Please label the diagram Renal artery Renal vein Kidney Explain the direc;on of the Ureter arrows Blood (oxygenated)flows from the aorta to the kidneys through the renal arteries The deoxygenated blood leaves the kidneys via the renal vein that runs into the inferior vena cava. Bladder Urethra opening The ureter Carries urine from the kidneys to the bladder. Urethra Kidney- transverse secDon Renal vein Nephron Collecting duct Add labels to the diagram Renal artery Cortex What is Dowing in the Renal column direc;on of the arrows? Urine Renal capsule - fibrous coating around the kidney Major calyx & Renal pyramid / medulla Ureter Renal pelvis  A kidney nephron Each kidney contains around 1.2 million nephrons. They remove toxic waste by filtering. Efferent arteriole - blood from glomerulus ↑ Please label the diagram S Afferent arteriole - Blood to glomerulus With the aid of the arrows explain blood Dow through the nephron / Glomerulus Blood (oxygenated) enters the kidney through the renal artery, blood flows into the glomerulus a tiny 2 filter made up of a knot of capillaries. Collecting duct- collects Blood (deoxygenated) exits the glomerulus through urine from the nephron. efferent arterioles which divide into peritubular capillaries. Blood flows through the peri-tubular Tubules W capillaries which are arranged around the renal tubule. The small veins join to form the renal vein Loop of here which carries blood away from the kidney. Video of urinary system https://www.youtube.com/watch? v=82mW8bpcSyU Renal Function Renal func;on is needed to : Maintain normal Essen;al for body Duid excre;on of volume and waste products composi;on and drugs FuncDons of the kidney Excretory Regulatory Forming urine to remove waste products Water and electrolyte to ensure not too many/ right amount. Homeostasis Endocrine Metabolic Metabolises vitamin D, this is a steroid hormone Producing hormones - renin & produced by the kidney.Controls the erythropoietin concentration of calcium in the blood development of strong bones. FormaDon of urine- 3 processes involved Filtra;on Selec;ve reabsorp;on Tubular secre;on Video of FiltraDon hRps://www.youtube.com/watch?v=9A2dAyWyK6o Epithelia cells shapes are different, wider to incrzease blood pressure within the capsule to Maximise passage of water and small substances. This is where filtration happens Glomerular Capsule Where Fltra;on takes place FiltraDon Water, & small molecules pass through the semipermeable walls of glomerulus and glomerulus capsule Larger molecules , blood cells, plasma proteins remain in capillaries SelecDve reabsorpDon Takes place in tubules Cons;tuents needed by the body are reabsorbed back into the blood capillary Ac;ve transport takes place at carrier sites in the epithelial membrane Energy is needed to transport substances against their concentra;on gradients Renal threshold– if all carrier sites are full substances will appear in urine which don’t normally e.g. glucose ReabsorpDon regulated by hormones Parathormone and calcitonin together regulate reabsorp;on of calcium & phosphate -vasopresen An;diure;c hormone increases water reabsorp;on by increasing the permeability of the convoluted tubules Aldosterone increases the reabsorp;on of sodium & excre;on of potassium. Angiotensin II a vasoconstric;ng hormone Tubular secreDon Some substances not required or in excess to body’s need may remain in blood aeer Fltra;on due to speed of Fltra;on e.g. hydrogen ions, drugs- penicillin, aspirin These are ac;vely secreted into the convoluted tubules Energy is required  What happens : blood filtration - blood enters the glomerulus under high ' Composition of pressure, forcing substances urine ; through the Glomerular Water 96% capillary into the nephron. Urea 2% filtration - the leaky Creatinine endothelial capsular membrane Ammonia acts like a sieve, allowing Sodium small substances to pass Potassium 2% through into the nephron. large Chlorides molecules such as plasma Phosphates Sulphates proteins remain in the blood. Oxalates selective reabsorption - as the filtrate moves through the renal tubule, the body reabsorbs Glomerular filtrate is the fluid that results from the filtration of needed substances and some blood by the kidneys. Which is the first step in urine production , Describe what happens to the glomerular Fltrates water. the process of glomerular filtration removes waste and excessive List the composi;on of urine urine formation/ secretion - the fluid from the blood and into the kidneys urine collecting tubules. substances that are not ribs absorbed leave the body in urine. How the kidneys maintain water balance Vital role of kidney is to maintain balance of water to ensure the body isn’t over saturated or dehydrated Water balance Food Body gains water from Drink Body loses water in Byproduct of metabolism Urine Faeces Perspira;on I sweat Expired air Water regulaDon by anDdiureDc hormone hRps://www.youtube.com/watch?v=I_RQLl3uyoI&t=86s 18 minutes ADH levels are adjusted based on Antidiuretic hormone also known as vasopressin, the concentration of blood plasma, is secreted by the posterior pituitary. It increases the when blood plasma is too permeability of the distal convoluted tubals and concentrated ADH levels increase, collecting ducts, increasing water resorption. causing the kidneys to re-absorb Osmoreceptors in the hypothalamus monitor the more water and produce less urine. water content of the blood and anti-diuretic This helps to return blood plasma hormone is adjusted accordingly by being concentration to normal.. regulated by the negative feedback mechanism. When ADH levels are too high, the body retains too much water and sodium levels in the blood may drop. When ADH levels are too low, the body produces too much urine. Electrolyte Balance Sodium & potassium Calcium balance Parathyroid and calcitonin Ingested in food hormones co-ordinate calcium balance PTH acts on kidney tubules Excess excreted in urine to reabsorb calcium Hormone aldosterone regulates Calcitonin acts on kidney excre;on of Sodium tubules to absorb less calcium  Self assessment With the aid of Ross & Wilson Explain how the nephron Flters the blood Describe homeostasis of water balance & electrolytes Now go back to Slides 4 & 5 and reassess your knowledge Useful References Waugh, A. and Grant, A. (2018) Ross & Wilson Anatomy And Physiology In Health And Illness. 14th ed. Elsevier. Ward, J. and Linden, R. (2017) Physiology At A Glance. 4th ed. Wiley-Blackwell. Extra videos hRps://www.youtube.com/watch?v=SVqSqPOcahY&feature=emb_rel_pause Detailed (45mins) of blood Fltra;on in capsule