Question

question 3 which molecule moved across the \cell membrane\ in the diffusion lab experiment? starch water iodine oxygen

Explanation:

In diffusion lab experiments with semi - permeable membranes, starch is too large to pass through. Water can move by osmosis which is a type of diffusion. Iodine can diffuse across if the membrane allows it due to its relatively small size. Oxygen can also diffuse across cell membranes in general biological systems. But commonly in simple diffusion lab set - ups with artificial membranes, iodine is often used to show diffusion as it can be easily detected by color changes when it reacts with starch.

Answer:

C. Iodine