What determines the efficiency of diffusion throughout the model “cells”?

The smaller the cells, the more efficient diffusion will be.

1. In terms of maximizing diffusion, what was the most effective size cube that you tested?

It was the smallest cube, that was 1 centimeter cubed, that had maximized the diffusion.

2.   Why was that size most effective at maximizing diffusion?  What are the important factors that affect how materials diffuse into cells or tissues?

The most effective was the smallest cube because it had a very small amount of volume which allowed the diffusion to be easily carried out all throughout the cube itself. Furthermore, it had a large surface area to volume ratio which allows diffusion to be the most effective. Additionally, temperature, concentration, type of material, size of the cell, and polarity are all factors that affect how materials diffuse into cells or tissues.

3. If a large surface area is helpful to cells, why do cells not grow to be very large?

A cell does not grow because if it did then the volume would get much larger which would result in a decrease in the surface area to volume ratio. A decrease in the ratio would result in a less effective diffusion and would take much longer for the process of diffusion to occur. In addition, there is less cell membrane for substance to diffuse through, meaning that the center of the cell is not receiving its necessary substances.

4.   You have three cubes, A, B, and C.  They have surface to volume ratios of 3:1, 5:2, and    4:1 respectively.  Which of these cubes is going to be the most effective at maximizing diffusion, how do you know this?

The most effective will be the 4:1 ratio, cube C, because, as stated above, the larger ratios are the ones that with hold the most maximization for diffusion. The smaller the cell (bigger the ration) the more adequate it is to have substances moving in and out of it.

5.   How does your body adapt surface area-to-volume ratios to help exchange gases?

Our bodies have larger organs that have a large surface area, meaning that it also has a large surface area : volume ratio. To have the good ratio we must have respiratory organs, such as lungs to have that gas exchange (oxygen in – carbon dioxide out).

6.   Why can’t certain cells, like bacteria, get to be the size of a small fish?

They cannot grow because once size increases the surface area: volume ration gets smaller. They cannot become larger because if that happens then the cell will no longer be efficient enough to bring enough nutrients and other things from the outside to the inside of the cell. Diffusion would not be able to occur throughout the whole cell.

7.   What are the advantages of large organisms being multicellular?

To begin multicellular organisms, have multiple different types of cells, while unicellular only cell. The multicellular organisms have special cells that deal with more difficult and understanding cells. Additionally, they have specific tasked organ systems such as the digestive, cardiovascular and respiratory systems. In order to survive it is crucial that these processes are done.