Co Transport in the ileum

• What is an isotonic solution?

  A solution with the same water potential
• What is a hypertonic solution?

  A solution with a lower water potential
• What is a hypotonic solution?

  A solution with a higher water potential
• What roles do villi and microvilli play in absorption?

  • Villi: 1 mm projections of the ileum wall
  • Microvilli: 0.6 μm projections on epithelial cells
  • Increase surface area for absorption
• What products are absorbed in the ileum?

  Glucose and amino acids
• How does the rate of transport across membranes increase?

  By different forms of membrane transport
• What is the difference between villi and microvilli?

  • Villi: 1 mm long
  • Microvilli: 0.6 μm long
  • Microvilli are over 1000 times smaller
• What is the function of microvilli in the ileum?

  Enhance diffusion and transport efficiency
• What is diffusion?

  Movement from higher to lower concentration
• Why does glucose move into the blood from the ileum?

  Due to a higher concentration in the ileum
• How does blood circulation affect glucose absorption?

  It maintains the concentration gradient
• Why is active transport necessary in absorption?

  To ensure complete absorption of nutrients
• What role does the sodium-potassium pump play in absorption?

  It maintains sodium ion concentration gradients
• Describe the process of co-transport in the ileum.

  1. Sodium ions actively transported out
  2. Higher sodium concentration in lumen
  3. Sodium ions diffuse back in via co-transport
  4. Glucose or amino acids are brought with them
• How do glucose and amino acids enter the blood plasma?

  Through facilitated diffusion
• What drives the co-transport process?

  The sodium ion gradient, not ATP
• What is the sequence of sodium ion transport in absorption?

  1. Sodium ions actively transported out
  2. Higher concentration in lumen
  3. Sodium ions diffuse back in via co-transport
  4. Glucose and amino acids enter blood