Biology Kidney structure

• What is the process of filtering blood in the kidneys called?

  Ultrafiltration
• How does blood enter the glomerulus?

  Blood enters the glomerulus through the afferent arteriole.
• Why does blood enter the glomerulus through the afferent arteriole?

  Because it is wider, maintaining a high blood pressure in the capillaries.
• What does the high blood pressure in the glomerulus facilitate?

  It pushes fluid from the blood into the renal capsule.
• What substances are filtered out of the blood during ultrafiltration?

  Water, amino acids, glucose, and urea.
• What remains in the capillaries after ultrafiltration?

  Blood cells and proteins.
• How does the low water potential in the capillaries affect water reabsorption?

  It helps reabsorb water later in the nephron.
• What is the function of nephrons in the kidneys?

  • Alter fluid composition from the renal capsule
  • Reabsorb essential nutrients back into the bloodstream
  • Secrete waste products in the distal convoluted tubule
  • Aid in maintaining a concentration gradient in the loop of Henle for water reabsorption
• What is selective reabsorption in the kidneys?

  It is the process of reabsorbing essential nutrients while secreting waste products.
• What mechanisms are involved in selective reabsorption?


  Active transport and cotransport.
• How do microvilli contribute to reabsorption?

  They increase the surface area for reabsorption.
• What type of proteins are involved in the cotransport of glucose?

  Cotransporter proteins.
• Why is there a high number of mitochondria in the cytoplasm of cells involved in reabsorption?

  To provide energy for the active transport process.
• How is a concentration gradient established for sodium ions?

  By pumping sodium ions out of the cells.
• How does glucose cotransport against its concentration gradient occur?

  It occurs through cotransporter proteins that utilize the sodium gradient.
• How does water move into cells during reabsorption?

  Through osmosis.