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.
Preliminary Experiments
One preliminary experiment was done before the main experiment. From
the preliminary, we were trying to find out how osmosis actually
occurred in potatoes, and gave us a vague idea on what the main
experiment would be like.
This preliminary will aid my prediction, which is stated below. The
following apparatus was used for the preliminary:
* 1 large potato (skin intact)
* 3 boiling tubes
* Set of cork borers
* Scalpel
* Balance (accurate to 2 decimal places)
* Distilled water
* 0.5M sucrose solution
* 1.0M sucrose solution
* Dropping pipette
* Boiling tube rack
* Measuring cylinder (accurate to 1cm3)
* White tile
Take a large uncooked potato, with the skin still on, and with the
cork borer, cut out three "tubes" of potato. Do this onto a white
tile, so you don't cut your fingers or wreck the bench. Take a ruler
and measure these tubes, and, if necessary, cut off any excess until
they are all the same length. The same potato must be used; otherwise
it will not be a fair test (because different potatoes may have
different osmotic properties).
To ensure the experiment is as safe as possible, ensure you don't
injure yourself using the cork borers. Also, we are using a sharp
knife, so caution is needed there. Even though the sucrose solutions
aren't poisonous, we are not 100% sure, therefore no sucrose solution
will enter us.
Weigh the three tubes of potato, and record down the mass. Take the
three boiling tubes, and fill 1 with 10cm3 of 1M sucrose solution, one
with 10cm3 0.5M sucrose solution and one with 10cm3 of distilled
water.
Label each tube clearly, then drop each potato tube into each boiling
Investigation of the Concentration and the Effect of Sucrose on Osmosis in Apple and Potato Tissues
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.
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 in Carrots Background Osmosis is the diffusion of water from a dilute solution to a more concentrated solution through a partially permeable membrane, which allows the pass of water molecules but not solute molecules. [IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE]If a cell is placed in a less concentrated solution water enters because the less concentrated solution will have a high concentration of water than the inside of the cell. Once the cell takes in maximum water the cell becomes turgid. If the cell was to be placed in a high concentrated solution, water would leave the cell because the cell would contain a low concentrated solution. So in the low concentrated solution there will be a high concentration of water and in the high concentrated solution there will be a low concentration of water.
* Note the mass down in the table at the end of the first page.
When I am not using them I will place them away from my experiment and
I am going to carry out an experiment to measure the change in mass of
The third potato chip will be placed in a hundred percent solution. I believe that this will make the potato chips shrivel and become flexible and stringy. This is because there is a higher concentration outside the cells and the water is being taken out to even the concentrations. This is what happens when a plant dies. The water leaves it in osmosis and the plant wilts and dies.
Size of potato-will be the same as it will be cut using a cork and borer which cuts them all to the same diameter.
the same way as it does potato. I would also widen the range of sugar
Equipment Potato, Borer, Beakers, Measuring Cylinder, Stopclocks, Distilled Water, Electronic Balance, Salt solutions of various concentrations. Diagram [IMAGE] [IMAGE] [IMAGE] When we leave the potato in the solution for the allocated time, water
The Effect of Solute Concentration on the Rate of Osmosis Aim: To test and observe how the concentration gradient between a potato and water & sugar solution will affect the rate of osmosis. Introduction: Osmosis is defined as, diffusion, or net movement, of free water molecules from high to low concentration through a semi-permeable membrane. When a substance, such as sugar (which we will be using in the experiment we are about to analyse), dissolves in water, it attracts free water molecules to itself, and in doing so, stops them from moving freely. The effect of this, is that the concentration of (free) water molecules in that environment goes down. There are less free water molecules, and therefore less water molecules to pass across a semi-permeable membrane, through which sugar molecules and other molecules attached to them are too big to diffuse across with ease.
there would be no flow of water into or out of the cell so the cell
== = This experiment is based on the concept of Osmosis. Osmosis is the diffusion of water molecules from a region of high water concentration to a low water concentration through a semi permeable membrane (in this case, the cell potato cell membrane). The cell walls of the potato cells are semi permeable meaning that water molecules (which are small) can fit through but other bigger molecules such as glucose cannot pass through. The water molecules can flow both ways through the membrane, letting molecules both in and out.
When you place a potato chip in a salt or sugar solution, then if the