Movement of molecules

Movement of molecules through the cell membrane

Start

Materials

Fehling-A and B solution

An electronic balance

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05

09

Two small semi-permiable bags

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10

A spoon

Two glass beakers

A measuring cilinder

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Two plastic containers

Three pipettes

Distilled water

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Iodine solution

Glucose powder

The objective is to simulate the functions of a semi-permiable cell membrane and to explore the differences in the movement of molecules into and out of a semi-permiable membrane

Objective

Step 3

Measure 1 ml of fehling A and put it in the second beaker

Step 4

Step 2

Measure 1 ml of fehling B and put it in the second beaker

Measure 2 ml of the iodine solution and put it in the first beaker

Step 1

Measure two times 50 ml of water with the measuring cilinder, then pour it in the beakers.

STep 5

Measure 5 grams of glucose and 5 grams of starch by using an electronic balance. Then put the substances in two different bags. Pour 20 ml of water in the bags and close them with bag clips. Put the bags in the beakers.

Step 6

Put the bags into the beakers and wait for results

Conclusion

At the end of the experiment, we should have seen the color change of the liquids in the beakers. As we did not warm up the beakers, we did not manage to get the right result.

The moleculas of starch and glucose should have passed through our semi-permiable membrane and react with Iodine and Fehling's solution, causing a color change, but the temperature wasn't high enough to see immediate results.