1. Formation of Urine & Water Balance 7.5, 7.6

2. First, some review…

4. What is this?

6. quizlet.com Remember this website? http://quizlet.com/1644286/homeostasis- terms-flash-cards/ this is a set of Homeostasis flashcards

7. How is urine formed?

8. Urine Formation (Image on previous slide from: http://www.mountainside-medical.com/products/Urine-Specimen-Cup,-Sterile.html) filtration reabsorption secretion

9. Filtration glomerulus high pressure: 65mm Hg smaller dissolved molecules can move through the walls of the glomerulus 600mL of blood flows through the kidneys each minute; 120mL is filtered

10. Reabsorption 119mL of every 120mL of glomerular filtrate is reabsorbed (phew!) 3 main substances reabsorbed: –water (passive) –all glucose (active) –Na + (active) also amino acids (active), Cl - and HCO 3 - (charge attraction), etc.

11. Secretion nitrogen-containing wastes (such as NH 3, urea, uric acid), H + ions, and K + ions are secreted in the distal tubule Simple animation on urine formation with no narration: http://www.kidneypatientguide.org.uk/site/HKWanim.php

12. Review This interactive animation has a nice feature where you can track the movement of various substances: http://www.biologymad.com/resources/kidney.swf Narrated animation on urine formation: http://davisplus.fadavis.com/scanlon6e/Animations/animations.cfm?exe rcise=NephronFiltration&title=Nephron%20Filtrationhttp://davisplus.fadavis.com/scanlon6e/Animations/animations.cfm?exe rcise=NephronFiltration&title=Nephron%20Filtration Narrated animation of structure & function; quite detailed: http://bcs.whfreeman.com/thelifewire/content/chp51/51020.html

13. 7.6 - Water Balance

14. Water Balance (Image on next slide from: http://knight.noble-hs.sad60.k12.me.us/content/exploringLife/text/chapter32/concept32.2.html) water balance (i.e. amount of water in the blood) is regulated by the hypothalamus osmoreceptors detect changes in blood solute concentration release of ADH (anti-diuretic hormone) increases water reabsorption

16. Blood Pressure Regulation blood pressure receptors in the juxtaglomerular apparatus release renin, which activates angiotensinogen angiotensin causes the adrenal glands to release aldosterone aldosterone is a hormone that acts on nephrons to increase Na + reabsorption in the distal tubule and collecting duct

17. (Image from: http://www.colorado.edu/intphys/Class/IPHY3430-200/017kidneys.htm)

18. pH balance cellular respiration produces CO 2 as a waste product CO 2 dissolved in the blood becomes H 2 CO 3 (carbonic acid) carbonic acid dissociates into H + (acidic) and HCO 3 - (basic)

19. pH balance

20. peritubular capillaries actively transport CO 2 to the tubules generates H + and HCO 3 - ions HCO 3 - ions diffuse back into blood H + ions combine with phosphate ions or ammonia and are removed by the kidneys

21. Images in Slides #3,4,5 Excretory system: http://faculty.ccri.edu/kamontgomery/anatomy%20lab_13%20ur ogenital.htm Kidney: http://www.dorenarode.com/anatomy/openlab.htm Nephron (colour): http://movies-ciarancolegage.blogspot.com/2011/03/kidney- diagram-labeled.html Nephron (unlabelled): http://kenpitts.net/hbio/46skel_musc_integ_systems/ch46_sched _08.htm