Agar Jelly Lab Report

Cells and molecules in the environment are constantly moving and changing, for cells to function properly there is a need for equilibrium to be met. The size of the cell and the solution outside of the cell affects the rate of diffusion and osmosis in the cell. Cells are constantly trying to reach an equilibrium with the molecules and substances around it, which is why there are such terms as: hypertonic, hypotonic and isotonic. The procedures allowed testing of whether or not surface area or volume increased diffusion and how different substance control diffusion. Cells are constantly moving to reach equilibrium through diffusion and osmosis.

A. The size of the molecule. The larger molecule will diffuse more slowly than the smaller molecule.

I know that osmosis will occur in the vegetables, but I am not sure of

The experiment proved my hypothesis correct that as the size of the Agar cube grows larger; the diffusion rate will be slower therefore taking up more time. The cubes were put into hydrochloric acid and left by, in order to exchange materials through diffusion, as a sample of cells in real life. As we can see the cube with the largest surface area and volume has the smallest surface area to volume ratio. If the surface area to volume ratio gets too small, then the substances won’t be able to enter the cell fast enough to fuel the reactions, because the surface area controls the rate of the exchange of materials while as the volume grows larger it will need more materials to enter and exit, in a more quicker rate, therefore waste products will start to accumulate within the cell as they will be produced faster than they can be excreted. In addition, the cells will not be able to lose heat fast enough and so may overheat. This was concluded from the experiment, where as the Agar cube dimension were larger, the rate of diffusion was much smaller from the Agar cube with the smaller dimension, where the last had a larger V: SA ratio than the larger cube.

7. Explain how incubation plant tissues in a series of dilutions of sucrose can give an

After conducting the Mello Jello lab during class this week, my group and I have discovered that Wisk laundry detergent is the best at breaking down foods, or in this case, the Jello. The results most likely ended up being this way because Wisk, I believe, has the most added enzymes which, therefore, makes it able to break down the sugars and some other molecules in Jello easier than the other detergents. Enzymes are a type of protein that acts as a catalyst and is able to cause a reaction that helps break down certain substances such as yeasts faster than they usually would be broken down.

A major determinant of diffusion in a biological system is membrane permeability. Small, uncharged molecules pass through cellular membranes easily, while most and/or charged molecules cannot pass through the membrane. The movement of water across a selectively permeable membrane, like the plasma membrane

1. The relationship between rate of diffusion/ osmosis, volume, and surface area can be easily seen and analyzed through the data that was collected from procedure one: Surface Area and Cell Size. Phenolphthalein is a dye-material in this lab that was used to determine whether a substance was an acid or base. This could be told as the phenolphthalein changed into a murky. Muddled and clouded color when mixed with acids. When the chemical aid was mixed in with a base, the color

▪ Surface area to volume ratios and the ability of cells to get nutrients in and waste products out of the cell

There were several steps completed to prepare for the experiment. Three dialysis tubes were filled with approximately the same volume of distilled water and then were tied shut. The initial mass (in grams) of the tubes was taken using a triple beam scale. I then filled three 500 mL beakers with 400 mL of water each and dissolved different masses of solute (table sugar) in each beaker in order to make 5%, 10%, and 20% solutions. The beakers were labeled accordingly, and then 20 g, 40 g, and 80 g (respectively) of table sugar was weighed out using a digital scale and placed into the corresponding beakers. The sugar was stirred in using a stirring rod until all of the solute was completely dissolved.

In order to assimilate diffusion through a permeable membrane potassium permanganate and methylene blue were used in experiment. The objective was to compare the rates at which the liquid compound of different molecular weight diffused through agar. This was achieved by obtaining agar in a petri dish with two wells to hold the liquid compounds. The rate was measured by time and diameter distance diffused. This process was observed for 60 minutes at 15 minute intervals.

Before beginning this experiment, the completion of an IRB Form and a Written Consent Form for the usage of human participants. After Bethel College agreed to approve this experiment, the testing began. The Bethel College Biology Department approved the materials needed for this experiment. These materials were easily attained from Wal-Mart located in Newton, Kansas which included: three bottles of Listerine Zero Total Care ®, two one hundred count packs of one ounce Kroger ® disposable bathroom cups, one two hundred-fifty count pack of Kroger ® plastic spoons, and one twenty-nine fluid ounce tub of Tropical Life ® Organic Extra Virgin Coconut Oil. The Bethel College Biology Department supplied a laboratory that housed the equipment needed

In conclusion, the potato cube with the highest surface area to volume ratio (the 1x1x1 cube) had the fastest rate of diffusion as it had the largest percentage increase in mass. While all the other cubes of potato had larger increases in mass at face value compared to the smallest cube, the smallest cube had the largest overall gain in percentage. The results support my hypothesis that the smallest cube will have a higher rate of osmosis because it has a proportionally larger amount of surface area compared to its volume.

Group 1 received 107% for 0.0m, 109% for 0.25m, 112% for 0.5m, and 126% for 0.75m. Group 2 received 100% for 0.0m, 107% for 0.25m, 116% for 0.5m, and 117% for 0.75m. Group 3 received 100% for 0.0m, 106% for 0.25m, 114% for 0.5 m, and 117% for 0.75m. Group 4 received 100% for 0.0m, 106% for 0.25m, 113% for 0.5m, and 116% for 0.75m. Group 5 received 98% for 0.0m, 105% for 0.25m, 110% for 0.5m, and 115% for 0.75m. Group 6 received 104% for 0.0m, 108% for 0.25m, 111% for 0.5m, and 104% for 0.75m. The trend line that occurred for the rate of osmosis was an upward increase as the solute concentration increased.

Data: Effect of Solute Concentration on Osmosis in Potato Cells (for the 6 groups of our class)