Kidney Video

• 25% of blood leaving the left ventricle enters the kidneys
• three layers of the glomerular capillary wall

  1.) endothelial

  2.) basement membrane

  3.) epithelial - contains foot processes
• some substances that can be filtered through the epithelial cell layer

  sugars, urea, amino acids
• intermediate sized proteins are blocked at the ________ ________ cell layer

  basement membrane
• large proteins are blocked at the __________ cell layer


  endothelial
• what are two forces that promote glomerular filtration?

  1.) P(BS) (10 mmHg)

  2.) pi plasma (20 mmHg)
• on average, 2/3 of filtered solutes and water is reabsorbed into the capillaries
• the descending limb is permeable to H2O which begins to concentrate the urine
• solute is transported out of the ascending limb
• which two solutes create the medullary concentration gradient?

  sodium chloride and urea
• ADH is released from the pituitary in response to dehydration, which makes the collecting duct permeable to water and urea; this helps to conserve water
• acidosis augments the secretion of H+ ions
• sodium reabsorption and K+ secretion can also take place in the distal tubule
• renin produces angiotensin, which controls the rate of aldosterone secretion
• aldosterone functions to increase the amount of Na+ reabsorbed and K+ secreted
• there are 1 million nephrons in each kidney