Active Absorption of Glucose in the Small Intestine

When the concentration gradient between the blood and the ileum is low, active methods may be used to absorb glucose into the blood

Co-transport proteins in the cell membranes of the cells lining the ileum

Sodium ions are actively pumped out of epithelial cells, into blood

Higher concentration of sodium ions in ileum than in epithelial cells

Sodium ions diffuse down the concentration gradient, into the epithelial cells, through a co-transport protein in the cell membrane

As sodium ions move into the cell, glucose molecules are coupled with them, carrying the glucose up the concentration gradient