The Effect of Different Strength of Salt Solutions on Potato Cells Through Osmosis
An Investigation to find out how different strengths of salt solution
affect potato cells through osmosis.
Aim
I aim to investigate the effect of different concentrations of salt
solution on potato cells when osmosis occurs.
Introduction
I intent to set up this experiment using equally sized cylinders of
potato submerged in salt solutions of different concentrations. I will
then observe the percentage change in mass over a set period of time.
This will show me how much osmosis has occurred.
Scientific Theory of Osmosis
Osmosis is defined as the solvent of any solution being able to pass
through any semi-permeable membrane from a region of high
concentration to a region of low concentration until both solutions
reach a state of equilibrium. This means that water can flow through a
porous material, such as a cell wall or visking tubing, in order to
balance the levels of concentration. The molecules are then randomly
distributed throughout the solution.
Water particles are small and can therefore easily fit through the
material; however, larger particles such as salt or glucose are too
big to fit through the material.
Osmosis has a significant effect on living cells. Animals cells will
burst in pure water because, as the cytoplasm is fairly concentrated,
the water, which is less concentrated, will enter the cell. As the
dissolved substances in the cytoplasm are larger, they cannot escape
so the cell becomes swollen and may burst.
If an animal cell is placed into a more concentrated solution, the
water in the cell will flow...
... middle of paper ...
...rmine the molar
concentrations. This would ensure an accurate amount of liquid in each
beaker. I could also weigh the cylinders on a more accurate scale, for
instance 0.0000g rather than 0.00g.
I could perhaps find a more accurate way of removing the excess liquid
from the potatoes after the experiment which is more accurate. Also, I
did not have time to repeat the experiment a second time. This would
be a good idea if I were to do the experiment again.
Only one of my results seemed to be slightly inaccurate. This could
have been because of a number of reasons. Maybe I didn't cut the
cylinders equally or the solution was inaccurate. Perhaps I did not
dry it as thoroughly as the other, which would have added to the mass.
With all this said I think my experiment went very well and I am
pleased with the outcome.
In this experiment I will use 5 potato chips, I 'm using potato chips because they have lots of cells in which will give us better results to explain osmosis. And will use five to give us more accurate and better results. I will make sure the potato chips are measured accurately, each weighing roughly the same size and making sure no excess skin is left on. Before placing the chips in the solutions I will measure them and record their results. I will then place the 5 potato chips in 5 separate test tubes filled with different concentrations.
other hand when an animal cell is put in pure water it will burst due
Conclusion In my conclusion, the potatoes with the lowest concentration gained the most mass, and would become hard relating back to the Turgor theory I stated earlier. In contrast to this, the potatoes in the most concentrated solution lost the most weight thus becoming plasmolysed and limp also relating back to the background I have mentioned earlier. Evaluation In general the experiment was succesful the results were consistent and also were in accordance with the theories made at the start.. The experiment could have been improved by: · More subjects used instead of potatoes · More potatoes · Wider time ranger · Different molarities Using this variety of methods could have improved the experiemnt, however I was generally satisfied with the results of this osmosis experiement.
This occurs when special carrier proteins carry solutes dissolved in the water across the membrane by using active transport. When the concentration gradient can not allow travel from one side of the membrane to the other fast enough for the cell’s nutritional needs, then facilitated diffusion is used. The transport protein is specialized for the solute it is carrying, just as enzymes are specialized for their substrate. The transport protein can be
* Note the mass down in the table at the end of the first page.
In osmosis, water can travel in three different ways. If the molecules outside the cell are lower than the concentration in the cytosol, the solution is said to be hypotonic to the cytosol, in this process, water diffuses into the cell until equilibrium is established. If the molecules outside the cell are higher than the concentration in the cytosol, the solution is said to be hypertonic to the cytosol, in this process, water diffuses out of the cell until equilibrium exists. If the molecules outside and inside the cell are equal, the solution is said to be isotonic to the cytosol, in this process, water diffuses into and out of the cell at equal rates, causing no net movement of water. In osmosis the cell is selectively permeable, meaning that it only allows certain substances to be transferred into and out of the cell.
I am going to carry out an experiment to measure the change in mass of
Water Potential of Potato Cells Aim: To demonstrate the Water Potential of Potato Cells. Objectives: · To show the water potential of potato cells using various measured concentrations of a sucrose solution and pieces of potato. · To record and analyse data to verify observed results. · The method and procedure was carried out as per instruction sheet. Observations: The experiment shows that the lower the concentration of the sugar solution, in the Petri dish, the mass of the potato increased.
Change Apparatus Top Pan Balance - to weight carrots Measuring Cylinders - to measure solution and distilled water Dropper Pipettes - to ensure accurate measuring of solutions Distilled Water - to test how osmosis works in carrots 1M Salt Solution - to test how osmosis works in carrots Carrots Disks - to weigh carrot mass in Beakers - to soak carrots in Goggles - to protect eyes Diagram Method Using a measuring cylinder and dropper pipette I accurately measured 50cm³ of distilled water and 1M solution of sodium chloride then separately poured them into two separate beakers. The beakers were of
Investigating the Effect of Sugar Solution on the Weight and Size of Potato Cells Aim: To investigate whether the different concentration of sugar solution will affect the weight and size of the potato cells. General background information: Osmosis is defined as the movement of water or any other solution's molecules from an area in which they are highly concentrated to a region in which they are less concentrated. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules (E.g. water) through but does not allow larger solute molecules to pass through. The molecules will continue to diffuse until the area in which the molecules are found to reach a state of equilibrium, meaning that the molecules are equally distributed throughout the cell, with no area having a higher or lower concentration than any other hence equal. Hypothesis/prediction: For this particular investigation I believe that the lower the concentration of the sugar solution in the test tube the mass of the potato will be greater and the longer the potato cells will be.
Investigating The Effect Of Concentration Of Salt Solution On The Mass Of Potato Chips Aim: The aim of this investigation is to see whether the amount of salt solution affects the mass of the potato chip Hypothesis: In the solution below, water will diffuse from the dilute solution into the concentrated solution through the process of osmosis. Therefore the dilute solution level will fall and the concentrated level will rise Line Callout 2: Disapproved (is unable to go through the semi permeable membrane O Line Callout 2: Approved (is able to go through the semi permeable membrane P Salt solution Water [IMAGE] When a substance such as salt dissolves in water, the substance's molecules stick with some of the water molecules, so the concentration of the water molecules decreases. When the water molecules are the same concentration on both sides of a semi permeable membrane and salt is dissolved into one of them, osmosis will occur as shown in the diagram below.
Determining the Concentration of the Cell Sap in Potato Storage Tissue Aim: To determine the concentration of the cell sap in potato storage tissue. By using Osmosis, determine what the sugar concentration of cell sap is. Prediction I predict that the potato segment in the distilled water will definitely gain in weight because the solution outside it has a much higher concentration of water then in the cell sap meaning Osmosis will occur and the potato segment take in water. I predict that 0.2M sugar solution will also gain weight because it still has quite a high concentration of water outside the potato. The potato in the 0.4M solution will gain weight but the potato in the 0.6M and 0.8M solutions will lose weight.
We then cut our potato tubes with the cork borer and cut them with the scalpel so they were the same length and weighed them. We then put one potato tube in each test tube and then added the same amount sugar solution in to each tube. The concentration of sugar solutions varied in each test tube.
Osmosis is the movement of water molecules from a dilute solution (has a High Water Potential) to a more concentrated. solution (has a Low Water Potential) through a selectively permeable. membrane in order to achieve equilibrium. A membrane that allows water. to pass through, but not solute molecules.
Prediction I think that when the potato is placed in distilled water the potato mass will increase. This is because water, has, if pure, a weaker concentration than the potato, and the water molecules move in through a partially permeable membrane by osmosis. If the potato is in a high concentration salt solution, the potato mass will decrease because the potato is less concentrated than the salt solution, and the water will move through the partially permeable membrane into the stronger solution. However, if the potato mass stays the same after the experiment, this means that the water/salt solution and the potato must be of equal concentration.