1 / 11

Excretory System

11.3 The Kidney Learning Targets: Define excretion and osmoregulation. Label structures and explain functions of the kidney and the nephron in ultrafiltration and reabsorption. Excretory System. Renal arteries – carries blood to kidneys from heart Renal veins

carrie
Download Presentation

Excretory System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 11.3 The KidneyLearning Targets: Define excretion and osmoregulation. Label structures and explain functions of the kidney and the nephron in ultrafiltration and reabsorption.

  2. Excretory System • Renal arteries – carries blood to kidneys from heart • Renal veins – carries blood from kidneys to heart • Ureter – collects urine (water and metabolic wastes) • Bladder – stores urine delivered by ureters

  3. Excretory System Excretion – the removal from the body of the waste products of metabolic pathways.

  4. Kidney • Renal cortex • Renal medulla • Collecting ducts • Renal pelvis • Ureter

  5. Osmoregulation Osmoregulation - the body’s response mechanisms which attempt to maintain homeostatic levels of water.

  6. Nephron • Nephrons are kidney structures that help mammals conserve water – almost 99% of water and solutes are reabsorbed (wastes are excreted)

  7. Basement membrane • Glomerulus • Blood pressure forces fluid out of blood in this ball of capillaries 2. Bowman’s capsule • Receives water and small solutes (salts, glucose, vitamins, urea) through “ultrafiltration” from glomerulus

  8. NaCl Glucose H2O 3. Proximal tubule • Regulates pH by secreting H+ and absorbing HCO3- • Pumps NaCl and nutrients out of filtrate, H2O follows by osmosis 4. Descending Loop of Henle • Permeable to water but not solutes • Medulla has high urea concentration so water leaves Active Passive Increasing Solute Gradient H2O

  9. NaCl Glucose H2O H2O NaCl 5. Ascending Loop of Henle • Permeable to salt, not water • NaCl leaves (passive and active) 6. Distal tubule • Regulates pH by secreting H+ and absorbing HCO3- • Pumps out salt, water follows Active Passive Increasing Solute Gradient NaCl H2O

  10. NaCl Glucose H2O H2O NaCl 7. Collecting duct • Pumps out salt, water follows • Urea diffuses out to raise solute concentration in medulla Active Passive H2O Increasing Solute Gradient NaCl H2O Urea

  11. NaCl Glucose H2O H2O NaCl 7. Collecting duct • Regulated by ADH (antidiuretic hormone) secreted by pituitary (region of brain) • Salt or dehydration triggers release of ADH • Body responds with thirst, collecting duct becomes more permeable to water (body reabsorbs more water) Active NaCl Passive H2O Increasing Solute Gradient NaCl H2O Urea Urea Urea

More Related