The variables to be controlled in this experiment are: the total amount of sucrose solution used, the size and shape of the test tubes used, the type of water used in this case, it will always be distilled , the potato tuber used to collect potato samples for one particular set of results , the length and circumference of the cork borer used the type of weighing. When the potato was distributed into 0. One can see that it does not fit the curve of best fit I drew; it shows the same change in mass as that of the 0. The two variables in this experiment would be the different molarities of the sugar solutions and the changing weight of each potato sample. Also, the equipment we used had uncertainties, which means that the equipment we used might not be accurate.
I think my results are fairly reliable because I did three repeats and took an average; however, the pieces of potato at the start varied in mass slightly; I found it was impossible to get them all to exactly the same mass without changing the length. Hence, the process requires expenditure of energy, and the support of a carrier protein. This would make the potato hypersonic. My results match my initial prediction, where I stated that I thought that osmosis would decrease as the molarity of the solution increases. This is the point at which the potato is isotonic with its surroundings, and is therefore the estimated salt concentration of the potato. Therefore we should use another substance that would have less net movement happening due to ionic forces, such as sugar.
PlanWater passes into cells through a special type of diffusion called osmosis. The time taken for all potato cylinders will be 30 minutes. The amount of solution I cover each chip in will be 30ml. Introduction - Osmosis is the process by which water molecules move from a region of low solute concentration to an area of high solute concentration through a semi permeable cell membrane until the concentration of water molecules in and out of the cell is at equilibrium. If you put a piece of potato into pure water, the water concentration is obviously higher outside the potato.
In this investigation, the mass of the potato only changed very slightly, and the differences in the changes of mass were also small. In the centre of the cell, there is the vacuole which contains the solution of salts, sucrose etc. Investigation of Factors Affect Osmosis in Potatoes Aim The aim of the following experiment was to investigate the effect of varying the concentration of sucrose solution on osmosis in a potato. Slice and weigh potatoes c. Therefore the distilled water solution will has the greatest mass and the higher the concentration that the chip is exposed to, the more water will move out of the chip; making it flaccid so the 10% chip will become flaccid. There was no way I could have rectified this, but it did affect the reliability of my results.
The next day, the potato slices were to be taken out and measured again. Maintaining all variablesunchanged such as the pH, same size, and a constant temperature. « Light: The light intensity will be mostly constant as the chips will not be moved whilst being stored. The results below show the preliminary results as you can see they are inaccurate. If we were to prepare a solute with the same concentration as the potato, 0.
Predict what would happen to the mass of each bag in this experiment if all the bags were placed in 0. The graph which looks more accurate is the one I will analyse. This is to find the equivalent osmotic potential. We will measure the mass of a potato cylinder after a certain amount of time in a certain solution. If the potatoes all had the same mass, then results would be more specific and accurate.
Å¸ The concentration of the sugar solution. This liquid or hydrostatic pressure works against osmosis. A living system also contains an active transport to create movement of particles like ions that move against their concentration gradient. Soak the potato in the beaker for 20 minutes. Graph the increase and decrease in mass of the potato cores according to the molarity of the solutions they were placed in on graph 1.
Tie off one end securely. Measure the mass of each potato cylinder using top-pan balance and record it. The book 'Biology For Life' by M. The water the solvent can move across the membrane but the dissolved solutes the sodium and chloride ions that form salt cannot. Record the mass of each baggie in the data table. The next, 10%, looses approximately 0.