BIO 44

• What regulates urination?


  sphincter muscles
• Outer renal cortex and an inner renal medullaSupplied with blood by a renal artery and drained by a renal vein?

  kidney components
• Have tightly packed excretory tubules and associated blood vessels?

  cortex medulla
• Carry and process a filtrate produced from the blood entering the kidney?

  excretory tubules
• What happens to most of the fluid in the filtrate??

  reabsorbed
• What happens to a small majority of the fluid in the filtrate??

  urinate
• The basic filtering units in the kidneysWeave back and forth across the renal cortex and medulla?

  nephron
• 85% of all nephronsReach only a short distance into the medulla?

  cortical nephron
• Extend deep into the medulla?

  juxtamedullary nephron
• What does each nephron consist of??

  long tubule
• What does the blind end of the tubule form??

  bowmans capsule
• Retain blood cells and large molecules, such as plasma proteins, but are permeable to water and small solutes?

  glomerular capillaries
• When does processing of the filtrate occur??

  regions of nephron
• A hairpin turn with a descending limb and an ascending limb?

  loop of henle
• What receives the processed filtrate from the nephron??

  collecting duct
• How is each nephron supplied with blood??

  arteriole
• An offshoot of the renal artery that branches and forms the capillaries of the glomerulus?

  afferent arteriole
• What do the capillaries form as they leave the glomerulus?


  converge
• Formed from the capillaries of the glomerulusSurrounds the proximal and distal tubule?

  peritubular capillaries
• Formed from the capillaries of the glomerulus that extend downwardsHairpin-shaped capillaries that serve the renal medulla, including the long loop of Henle of juxtamedullary nephrons?

  vasa recta
• How much blood flows through a pair of human kidneys every day??

  1600
• How much filtrate is yielded daily??

  180
• How much of the filtrate actually become urine??

  1.5
• What happens in the proximal tubule??

  NA+ and Cl- reabsorbed
• What does the processing of filtrate in the proximal tubule helpmaintain??

  constant ph
• How do the cells of the transport epithelium keep the pH of body fluids constant??

  secrete H+
• What happens to materials that are to be excreted when the filtrate passes through the proximal tubule??

  concentrated
• Urea reabsorption rate compared to water and salt?

  lower
• Where does the filtrate go upon leaving the proximal tubule??

  loop of henle
• First portion of the loop of Henle?

  descending limb
• What is the descending limb not permeable to?

  salts
• What conditions need to be present for water to move out of the tubule by osmosis??

  hyperosmotic
• Why is water able to move out of the tubule by osmosis along the entire length of the descending limb??

  interstitial fluid increase
• What do the permeabilities of the descending limb mean for the filtrate??

  less water, more solution
• Where is the highest osmolarity in the loop of Henle found?

  At the elbow of the loop of Henle
• Where does the ascending limb take??


  cortex
• How does the ascending limb differ from the descending one??

  ascend lack water
• What happens as filtrate ascends in the thin segment??

  diffuse out of permeable tubule
• What does the movement of NaCL help do?

  maintian osmolarity
• Overall, what happens to the filtrate as it travels up the ascending loop??

  more dilute