Module 2: Epithelial Transport

Question 1

What is epithelial transport

Answer 1

movement of substances across two plasma membranes, one entering the cell and one leaving the cell

Question 2

What is a lumen

Answer 2

The hollow opening in the center

Question 3

What is absorption

Answer 3

transport of materials into the internal environment from the external environment

Question 4

What is secretion

Answer 4

transport of materials from the internal environment to the external environment

Question 5

What is the apical side

Answer 5

the side that faces the lumen, or inwards

Question 6

What is the basolateral side

Answer 6

the side that faces the blood/interstitial fluid, or outwards

Question 7

How do substances move through the epithelial cell

Answer 7

brought into the cell through the apical membrane and they are transported out of the cell through the basolateral membrane

Question 8

Sodium transport

Answer 8

Concentration of sodium is greater in the lumen of the small intestine than in the epithelial cells that line the small intestines, so the sodium naturally wants to move down its concentration gradient, enters through apical membrane and pumped out at the basolateral membrane

Question 9

Water transport

Answer 9

When the body needs to absorb water, epithelial cells actively pump solutes from the basolateral membrane of the cell into the ISF via aquaporins

Question 10

Glucose transport

Answer 10

the concentration of glucose is smaller in the lumen than in the epithelial cells, so glucose has to be actively transported into the cell at the apical surface - once the glucose is inside of the cell it has to exit the cell and enter the interstitial fluid by crossing the basolateral membrane