Question

A difference between the dialysis tubing used to in the lab to simulate a restrictive barrier and the phospholipid bilayers that surround living cells is:

a) The phospholipid bilayer restricts movement of ions and molecules based exclusively on their size.

b) The dialysis tubing restricts movement of ions and molecules based exclusively on their relative polarities.

c) The phospholipid bilayer restricts movement of ions and molecules based exclusively on their relative polarities.

d) The dialysis tubing restricts movement of ions and molecules based exclusively on their size.

e) None of the above

Answer 1

d) The dialysis tubing restricts movement of ions and molecules based exclusively on their size.

The dialysis tubing uses cellulose membranes in place of the phospholipid-bilayer membranes to separate the components of blood. The pore size of cellulosemembrane determines the size of the particles that will be able to pass through the membrane.

phospholipid bilayer is semipermeable, it selectively permits the flow of certain molecules across the membrane