Question

A student is investigating cellular transport and how it helps maintain homeostasis in living systems. The student completes the following steps:



1. Add 2 g of glucose and 2 g of starch to distilled water. Stir the mixture and pour it into a piece of dialysis tubing, which is used to represent the semipermeable cell membrane.



2. Seal both ends of the dialysis tubing, and rinse the outside of the tubing.



3. Place the dialysis tubing in a beaker of distilled water.



4. After 30 minutes, remove the dialysis tubing from the beaker.



5. Test for the presence of starch and glucose in the beaker and the dialysis tubing.





The student found that there was starch and glucose inside the dialysis tubing, while there was glucose but no starch inside the beaker.



Which of the following diagrams would be best for the student to include in his lab report to represent what occurred when the dialysis tubing was placed in the beaker?

A.
image 700620867e89434986781ba76d5eedd5

B.
image 7902e373469b4704b7f3d73595941920

C.
image 101d134d98704b769f83796e0f854442

D.
image 43ac959edb094af9ab336bbf8a2a6399

Answer 1

I can’t view the pictures you attached, but the correct diagram is the one that shows:
- Small glucose molecules passing through the dialysis membrane into the beaker (glucose present both inside the tubing and in the beaker, with arrows showing diffusion out), and
- Large starch molecules remaining inside the tubing (no arrows showing starch crossing).

Reason: dialysis tubing is semipermeable — small solutes like glucose diffuse out down their concentration gradient, while large polymers like starch cannot cross.

If you can describe each labeled diagram (A–D) briefly or re‑upload them, I’ll tell you which letter matches that description.