REABSORPTION OF GLUCOSE

• ADAPTIONS OF EPITHELIAL CELLS OF PROXIMAL CONVOLUTED TUBULE?

  • MICROVILLI: large SA to reabsorb from filtrate
  • INFOLDINGS AT BASES: large SA to transfer reabsorbed substances into capillaries
  • HIGH MITOCHONDRIA DENSITY: provide ATP for active transport
• PROCESS?

  1. Na+ actively transported out of epithelial cells lining the proximal convoluted tubule
  2. Creates concentration gradient
  3. Na+ diffuse down concentration gradient from lumen of proximal convoluted tubule into epithelial lining cells (through carrier proteins via facilitated diffusion)
  4. Each protein also carries another molecule (co-transport of glucose/ AAs)
  5. Molecules co-transported into cells of proximal convoluted tubule then diffuse into blood by facilitated diffusion