Co-transport and Absorption of Glucose in the Ileum

Question 1

What part do villi and microvilli play in absorption?

Answer 1

-Villi and Microvilli increase the surface area for absorption, as well as increasing the number of available carrier proteins and protein channels in a given membrane

Question 2

How are the products of carbohydrate digestion absorbed in the ileum?

Answer 2

-Glucose concentration increases
-Concentration gradient is created down which moves via facilitated diffusion from ileum into the blood
-Concentration gradient is maintained via blood ciruclation

Question 3

What are the roles of active transport and co-tansport in the absorption of glucose from the ileum into the blood?

Answer 3

ACTIVE TRANSPORT
-After facilitated diffusion, the concentrations are roughly equal in the ileum cells and the blood
-Active transport ensures that all the glucose and amino acids are still absorbed into the blood

CO-TRANSPORT
-Sodium ions are actively transported out by the sodium-potassium pump along with glucose or amino acids