home


 * Movement In & Out of Cells**

__**Exploration 4A**__

Out of the five different tubes of beetroots and their respective content, Tube A has the highest value of light transmitted while Tube C has the lowest. In between these two extremes are Tube D with the second highest value, followed by Tube E and B.
 * //Results//**
 * **Tube (Content)** || **Value of Light Transmission/cd** ||
 * A (4//ml// water [control]) || 95.0 ||
 * B (4//ml// of 25% alcohol) || 89.4 ||
 * C (4//ml// of 50% alcohol) || 31.6 ||
 * D (4//ml// of hot water) || 94.6 ||
 * E (4//ml// of water [diced beetroot]) || 93.2 ||
 * //Analysis//**

Tube A has the highest value of light transmitted at 95.0cd. This is followed by Tube D at 94.6cd, Tube C at 93.2cd, Tube D at 89.4cd and finally, Tube C at 31.9cd.

From the results, we can see that the amount of alcohol within content of the tube in which the beetroot is submerged in is the main determining factor of the value of light transmission. This is because Tube C, which has 3 slices of beetroot submerged in 4//ml// of 50% alcohol has the lowest value of light transmitted followed by Tube B which has 25% of alcohol in the 4//ml// of liquid. As the tube that contains the highest percentage of alcohol has the lowest value of light transmitted followed by the tube that contains the second highest percentage of alcohol, we can deduce that the amount of alcohol affects the value of light transmission.
 * //Discussion//**

Other than alcohol, we can see that the amount of surfaced area exposed is an affecting factor as well. The only difference between Tube E and Tube A is the size of the beetroot submerged within but Tube E clearly has a lower value of light transmission than Tube A. This is because Tube E contains diced up beetroot while Tube A, which is the control, contains 3 slices of 2mm thick beetroot.

Even though the amount of beetroot within the two tubes are the same, as diced up beetroot has a larger exposed surface area compared to the slices, more particles is able to escape from the beetroots into the liquid it is submerged in. When more particles move into the solution, the liquid would turn a darker color, hence lowering the value of light transmission.

Finally, we can determine that the temperature of the solution has the least effect on the value of light transmission. Tube D, which contains 4//ml// of hot water between 90°C and 100°C, only has a small difference in the value of light transmission when compared to Tube A, which is the control and contains 4//ml// of tap water.

Hence, the experiment shows that the alcoholic content of the liquid has the greatest influence over the value of light transmission, followed by the exposed surface area and finally, the temperature of the water.  __** Exploration 4B **__ __//2cm by 2cm Agar Block//__ __//1cm by 1cm Agar Block//__ __//0.5cm by 0.5cm Agar Block//__ Out of the three different sizes of agar blocks, the 64 smallest blocks, which is 0.5cm by 0.5cm in size, has the highest level of conductivity when compared to the other two sizes. At its peak, the level of conductivity is at 5.51 while the range is from 0.33 to 5.51. However, as 0.33 is before the the beaker of agar is being stirred, it can be considered as an outlier. Hence, the proper range is actually between 2.24 to 5.51. Both the range and the maximum value is higher than the other two sizes of agar blocks. //**
 * //Results//**
 * **Time/s** || **Level of Conductivity** ||
 * 0 || 0.22 ||
 * 10 || 0.15 ||
 * 20 || 0.32 ||
 * 30 || 0.45 ||
 * 40 || 0.66 ||
 * 50 || 0.65 ||
 * 60 || 1.18 ||
 * 70 || 0.91 ||
 * 80 || 0.83 ||
 * 90 || 1.91 ||
 * 100 || 0.94 ||
 * 110 || 1.07 ||
 * 120 || 1.10 ||
 * **Time/s** || **Level of Conductivity** ||
 * 0 || 0.61 ||
 * 10 || 0.43 ||
 * 20 || 1.76 ||
 * 30 || 1.63 ||
 * 40 || 2.43 ||
 * 50 || 1.80 ||
 * 60 || 2.50 ||
 * 70 || 2.19 ||
 * 80 || 2.8 ||
 * 90 || 2.29 ||
 * 100 || 2.47 ||
 * 110 || 3.38 ||
 * 120 || 2.22 ||
 * **Time/s** || **Level of Conductivity** ||
 * 0 || 0.33 ||
 * 10 || 2.24 ||
 * 20 || 2.46 ||
 * 30 || 2.68 ||
 * 40 || 3.16 ||
 * 50 || 3.41 ||
 * 60 || 3.92 ||
 * 70 || 3.88 ||
 * 80 || 4.20 ||
 * 90 || 4.41 ||
 * 100 || 5.51 ||
 * 110 || 4.60 ||
 * 120 || 4.83 ||
 * //Analysis

Following the 0.5cm by 0.5cm agar blocks are the 8 1cm by 1cm blocks. Although it has a lower level of conductivity than the smaller blocks, its level of conductivity is higher than the 2cm by 2cm blocks. Its maximum level of conductivity is 3.38 and has a range of 0.43 to 3.38.

Finally, the 2cm by 2cm block has the lowest level of conductivity. Its maximum level of conductivity is 1.18, which is lower than the two other sizes of agar blocks, and sports a range of 0.15 to 1.1.

From this, we can clearly deduce that the agar blocks’ level of conductivity is directly affected by the size, and hence exposed surface area, of the agar blocks. Although all three sizes of blocks are of the same volume of 4cm 2, the exposed surface area is different due to the differences in their sizes.

From this experiment, we can deduce that the level of conductivity is affected by the size and the exposed surface area of the agar block. //**
 * //Discussion

When the 4cm 2 agar block was cut into 64 smaller pieces of 0.5cm by 0.5cm, the surface area exposed to the tap water is greater than the surface area exposed by the 8 pieces of 1cm by 1cm block and is much greater than the 2cm by 2cm block. Also, its level of conductivity is the highest followed by the 1cm by 1cm blocks, and finally, the 2cm by 2cm block.

With this trend, it is clearly shown that as the exposed surface area increases, the level of conductivity would increase as well. As the level of conductivity of the agar is determined by the numbers of particles moving in and out of the agar block, a larger exposed surface area would allow more particles to move in and out of the agar into the tap water surrounding the cubes. This would hence increase the level of conductivity.