Co-Transport

Question 1

What is co-transport?

Answer 1

-type of facilitated diffusion that brings molecules and ions into cells together on same transport molecule

Question 2

How co-transport happens:

Answer 2

-glucose molecule and two sodium ions outside cell bind to carrier protein in cell membrane
-carrier protein changes shape and deposits glucose molecule and sodium ions inside cell
-glucose molecule and sodium ions separately diffuse through cytoplasm to opposite membrane
-glucose passes into blood by facilitated diffusion
-sodium ions carried out of epithelial cell by active transport by same carrier, moves potassium ions in, sodium conc remains low in epithelial cells-more sodium ions move in from intestinal lumen, bringing glucose in on the same carrier molecule