Finding the concentration of a Potato cell.

Figure 1: Percentage change in potato tuber mass vs. sucrose concentration. The percent change in mass decreased as the sucrose concentration increased. Relative osmotic concentration was measured as the percent change in mass of sucrose concentration over one hour.

Aim: To find the concentration of a potato cell cytoplasm compared to sucrose and salt. I mainly was looking to see how concentration of salt/sucrose affects the mass of the potato cores.

Purpose: To determine the concentration of solute in the potato’s cytoplasm by measuring the change

Though the theory following the hypothesis is correct and the experiment was carried out with as much attention as possible in a high school laboratory, the results obtained were still indicative of a few errors and did not support the predicted hypothesis. From the results obtained it can be concluded that as the concentration of sucrose increases the average percentage change in mass decreases. This is because the salt concentration inside the potato cubes of 10%, 15% and 20% concentration is less that in the salt concentration on the sucrose solution, thus the three cubes submerged in the 10% - 20% concentrated solution lost mass (hypertonic). However the cube submerged

The main purpose of the experiment was to test the idea that water would move from the higher concentration to the lower concentration. In order to test this theory, we placed potato slices in 7 different containers, each containing different concentrations of NaCl, to measure the weight change from osmosis. The containers ranged from 0M NaCl all the way to .6M NaCl. We measured the potato slices before and after placing the slices in the solutions and recorded the net change in weight to determine the tonicity of the potato cells. Our results showed that the potato slices put in a NaCl solution of .2M or higher lost weight and the potato slices put in a NaCl solution of .1M or lower gained weight. This shows that the osmolarity of the potato falls within the range of .1M to .2M, and it also proves the process of Osmosis by having the higher concentration move to the lower concentration. In addition to this, it can be concluded that the osmolarity of cells can be determined by observing the affects of osmosis.

However one beaker received 100 mL of Deionized water with a molarity of 0.0. Afterwards a cork borer was pushed through the potato and was twisted back and forth. Once the borer was filled it was removed from the potato. Pushing the potato cylinder out of the borer, this this step was repeated six more times in order to get seven undamaged potato cylinders. Using a sharp razor blade, the potato cylinders were both cut to a uniform length of about 5cm, and were removed of their potato skins. The potato pieces were also cut in half to give the cells a greater surface area in which it was easier to absorb the solution. After the cylinders were weighed on a balance and the data was recorded in Table 4. Using the razor blade each potato was cut lengthwise into two long halves. Then the potato pieces were transferred to the water beaker and the time they were submerged was recorded. This step was repeated for all potato cylinders in which the pieces were placed in solutions 0.1 to 0.6 M. The potatoes were incubated for ninety minutes. At the end of the incubation period the time was recorded. Then the potato piece was removed form the first sample. Next potato pieces were weighed the and the final weight was recorded in Table 4. This procedure was repeated until all samples had been weighed and recorded in the chronological order they were initially placed in the test solution. Afterwards the table was completed by recording the

Osmosis is defined as the tendency of water to flow through a semipermeable membrane to the side with a lower solute concentration. Water potential can be explained by solutes in a solution. The more positive a number is more likely it will lose water. Therefore should water potential be negative the cell the less likely it will lose water. In using potatoes the effects of the molarity of sucrose on the turgidity of plant cells. According to Clemson University, the average molarity of a White potato is between .24 M and .31 M when submerged in a sorbitol solution. This experiment was conducted with the purpose of explaining the relationship found between the mass in plants when put into varying concentrations of sucrose solutions. Should the potatoes be placed in a solution that contains 0.2M or .4M of sucrose solution it will be hypotonic and gain mass or if placed in .6M< it will be hypertonic and lose mass instead. Controlled Variables in this lab were: Composition of plastic cups, Brand of Russet Potatoes, Brand of Sweet Potatoes and the Temperature of the room. For independent variable that caused the results recorded it was the different Sucrose concentrations (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M). The dependent variable was the percentage change from the initial weighs to the final. The cup with .4 molarity was the closest to an isotonic solution and was used as the control group for the lab. Water potential is the free energy per mole of water. It is

This means that in the potato cells, water molecules will move in or out of the cell depending on the concentration of the sucrose solution and the water potential that the cell has. The process of water molecules moving out a cell is called exosmosis and the process of water moving into a cell is called endosmosis. Endosmosis occurs when the water potential

In conclusion when the molarity level was at 0 and at .2 the potatoes had gained mass so therefore they were placed in a hypotonic environments. When the molarity level was .4 and above the potatoes loss mass so therefore they were placed in hypertonic environments. So the different in concentrations does change the mass of the potatoes because they determine the osmosis environments.

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

An investigation of the glucose concentration of the cell sap in potato cells In this experiment I intend to investigate the effects of osmosis on potato cells. Specifically, I intend to use my knowledge of osmosis to investigate the glucose concentration of the cell sap in potato cells. Osmosis is a method by which water levels on either side of a semi permeable membrane may balance themselves. It occurs between regions of high water concentration and low water concentration.

As we can see in Figure’s 1.2 and 1.3, when there was no sucrose solution, the potato increased in weight. This is due to the fact that the sucrose solution was hypertonic in comparison to the potato slice. Through osmosis, the solution moved along the concentration gradient and into the potato slice making it hypotonic. When there were higher concentrations of sucrose solution, the potato decreased in weight. This is due to the fact that the potato was hypertonic in comparison to the potato. Through osmosis, sucrose from the potato moved along the concentration gradient out and into

In this experiment, the osmotic concentration is found with potato slices placed in sucrose solutions. Osmosis in this model is the net movement of water between the potato cell and the sucrose solution. The movement of water is determined by the molarity of sucrose. As the molarity of sucrose increased then the concentration in the solution also increased. H2O will move through the cell membrane to areas of higher concentration in order to reach equilibrium. If cells are placed

Effect of Sucrose Solution on Osmosis Aim: The aim of the experiment is to show how varying the concentration of sucrose solution affects osmosis by changing different molar solutions of sucrose and water and how it affects the potato. Introduction: In this investigation I will be exploring the effect of varying concentration of sucrose sugar solution on the amount of activity between the solution and the potatoes. Osmosis is the movement of water molecules across a partially permeable membrane from a high water concentration to a low water concentration.

Then, each group of students received the necessary materials to complete the experiment. When the students received the cups, they labeled cups to distinguish between the salt solution, distilled water, and control group. After weighing the cups and finding the mass of the cucumbers, the students poured 50 ml of water in one cup, 50 ml of salt solution in the other, and left the control cup empty. Then, the students placed the cucumbers into the cups and waited 30 minutes for the results. After the 30 minutes, the students removed the cucumbers from each solution and dried the cucumbers with paper towels. The students then weighed the cucumbers again and recorded their results. Lastly, the students found the difference from the original mass of the cucumbers and recorded their results.