1. To visualize diffusion of molecules across a semipermeable membrane To determine which molecules were permeable to the dialysis tubing To relate the diffusion of molecules across the dialysis tubing to diffusion across a plasma membrane To identify (3) factors that contribute

2. 1. Most hypothesized the following: a. Glucose moves out of the dialysis bag b. Starch moves out to the dialysis bag c. Iodine moves into the dialysis bag “Why did people think this would happen?” 2. A few hypothesized that starch molecules would not move out of the dialysis bag. “Why would a few think this?”

3.  Starch diffused out or stayed in bag – Iodine  Iodine reacts with starch and turns blue-black  Observe setup and complete Table 1  Glucose diffused out of bag – Benedicts Solution  Benedicts reacts with glucose and turn organge.  Add about two droppers of beaker water to test tube  Add Benedicts to test tube to make water blue  Place in hot water bath  Record observation in Table 2 Complete Analysis Questions #1-5

4. This is after the dialysis bag that was filled with a glucose and starch solution looked like after 60 minutes.

5. This is what the setup looked like after 24 hours.

6. This is a tube of beaker solution and Benedict’s solution. Note the orange color that looks like carrot juice. Yum, yum!