Why are cells so small ?
Claim:
We have concluded that the reason why cells are so small because if a cell has a large Surface area to volume ratio they are more efficient to diffusing essential nutrients. After conducting an experiment with our cubes we were able to come to this conclusion. In our experiment we had 3 cubes each with different dimensions. The first cube was 1 x 1 x 1, the next cube was 1.5 x 1.5 x1.5, and the last one 2 x 2 x2. For each cube we placed them in their own solution of vinegar for a total of 15 minutes. After that time, we measured how much of the cube was diffused by the vinegar. If there were some parts that were not completely diffused we measured the dimensions of how much of the cube was not clear.
Cell Diffusion Lab Poster
Cell Diffusion Lab Data
Cube Number
|
SA:V
|
Starting Volume
(cm3)
|
Ending Volume
(cm3)
|
% Diffused
|
One
(1x1x1 cm)
|
6:1
|
1
|
0
|
100
|
Two
(1.5x1.5x1.5 cm)
|
4:1
|
3.375
|
.48
|
85.8
|
Three
(2x2x2 cm)
|
3:1
|
8
|
1.32
|
83.5
|
(Note: The volume is related to how much of the cube had a pink tint to it. The ending volume is less because parts of the cube were clear. )
Based on our data we noticed that the only cube that was completely diffused was cube 1 during the 15 minute trial. This cube was also the one with the highest surface area to volume ratio to other cubes. As the surface area became higher it would take longer for diffusion to go on. For cubes 2 and 3 they were only able to diffuse 85.8% and 83.5% respectively. Both of those cubs had a smaller surface area to volume ratio then cell 1. Therefore, cells with a larger surface area to volume ratio are more efficient at diffusing essential nutrients.
Alternate Claim:
Another possible claim as to why cells are so small could be the following: The rate of diffusion is related to cell size, and nutrients diffuse at a faster rate through small cells than they do through larger cells. This claim is not accurate because, over 15 minutes, the rate of diffusion for all three cells was the same. In order to calculate the diffusion rate of the cells, we used the depth of diffusion, which was measured in each of the cells. The depth of diffusion was measured to be 0.4-0.5 cm in all sides of each of the cells. Due to the depth of diffusion being similar in each of the cells, the rate of diffusion would also be similar in each of the cells. Therefore, the claim that diffusion rate depends on the size of the cell is not accurate because we recorded data that proves that the rate of diffusion was the same within cells of different sizes.
No comments:
Post a Comment