Co Transport

Question 1

What does there need to be to absorb glucose from the lumen to the gut?

Answer 1

A higher concentration of glucose in the lumen compared to the epithelial cell (for facilitated diffusion) BUT there is usually more glucose in the epithelial cells- that is why active transport and co-transport are required

Question 2

1st step of co-transport?

Answer 2

Sodium ions are actively transported out of the epithelial cells into the blood using the sodium potassium pump

Question 3

2nd step of co-transport?

Answer 3

This reduces the sodium ion concentration in the epithelial cells compared to the ileum

Question 4

3rd step of co-transport?

Answer 4

Sodium ions can then diffuse from the lumen down the concentration gradient into the epithelial cell

Question 5

4th step?

Answer 5

The sodium ions diffuse through a co-transporter protein so either glucose/amino acids are attached and are transported into the epithelial cell
Glucose/amino acids move against the conc gradient
Sodium moves down its conc gradient

Question 6

5th step?

Answer 6

Glucose/amino acids move by facilitated diffusion from the epithelial cells into into the blood using