In an osmosis experiment using a dialysis tube filled with a starch and glucose solution, the dialysis tube was permeable to which substance?

• A. Glucose
• B. Neither glucose nor starch
• C. Both glucose and starch
• D. Starch

Answer: (A)

Verified step by step guidance

1. Understand the concept of osmosis and diffusion: Osmosis refers to the movement of water across a semipermeable membrane, while diffusion involves the movement of solutes. Dialysis tubing acts as a semipermeable membrane, allowing certain molecules to pass through based on size.
2. Analyze the molecular size of the substances: Starch is a large polysaccharide, while glucose is a smaller monosaccharide. The size of the molecules determines their ability to pass through the pores of the dialysis tubing.
3. Determine the permeability of the dialysis tubing: Dialysis tubing is designed to allow smaller molecules, such as glucose, to pass through while restricting larger molecules, such as starch.
4. Consider experimental observations: In an osmosis experiment, if glucose is detected outside the dialysis tube, it indicates that glucose molecules were able to diffuse through the membrane. Starch molecules, being larger, would remain inside the tube.
5. Conclude based on the evidence: The dialysis tube is permeable to glucose but not to starch, as the size of the starch molecules prevents them from passing through the semipermeable membrane.