Investigating Osmosis in Potato Tissue
Aim-We are going to investigate how 'osmosis' is effected by higher
and lower concentrations of water using potato cylinders as
selectively permeable membranes. A selectively permeable membrane is
something only water molecules can pass through.
We will cut eighteen potato cylinders to the same width and length
using a scalpel and a corer on a white tile. We shall use the same
potato for each cylinder. The cylinders should then be around the same
mass. The corer is used to get the actual shape (cylinder) and the
scalpel is used to cut off the bits of potato skin that may effect the
experiment. The scalpel has a thin and very sharp blade to ensure the
length is cut accurately. Each potato cylinder must be measured with a
ruler to ensure that they are all the same length when cutting the
skin off the top and bottom of each cylinder.
Same Diameter + Same Length = Same Surface Area
We will then weigh the potato cylinders and record their mass, using
electric scales (electric scales give very accurate readings to 2d.p),
and then place the potato cylinders into six specimen tubes, (three
potato cylinders in each one). Each specimen tube will have a screw
top to stop any of the solution evaporating. They will contain
different concentrations of water with six different amounts of
sucrose in them. Using a syringe or a pipette will make the
concentration of each solution, by adding the sucrose to the distilled
water. This will be done in a measuring cylinder to get the
appropriate amounts of distilled water and sucrose solution. Three
hours later we shall come back, weigh the potato cylinders and record
how the mass has changed in the last three hours.
This plan above is a good way of carrying out the task because osmosis
needs quite some time to take place, that's why we are going to leave
the experiment three hours before recording the mass change. Also
getting the shape of each potato cylinder is important because any
Investigating Osmosis In A Potato Introduction: "Osmosis is typically defines as the flow of one constituent of a solution through a membrane while the other constituents are blocked and unable to pass through the membrane. Experimentation is necessary to determine which membranes permit selective flow, or osmosis, because not all membranes act in this way. Many membranes allow all or none of the constituents of a solution to pass through; only a few allow a selective flow. In a classic demonstration of osmosis, a vertical tube containing a solution of sugar, with its lower end closed off by a semi-permeable membrane, is placed in a container of water. As the water passes through the membrane into the tube, the level of sugar solution in the tube visibly rises.
Osmosis in Potato Tubes Osmosis: Osmosis is the movement of water molecules through a semi-permeable membrane from a high concentration to a low concentration. Diagram: [IMAGE] [IMAGE] Aim: To see the effects of different concentration of sugar solution on Osmosis in potato tubes. Key factor: In the investigation we change the sugar solution from: 0%-10%-20%-30%-40%-50% this is the independent variable; the dependant variable is the change in mass. Prediction: I predict that all the potato tubes in pure water or low concentration sugar solution will swell because water enters their cells by osmosis.
Method: [IMAGE] Equipment needed: Ruler Measuring Cylinder Scalpel Tongs Pipette Thermometer Tri-pod Stop-clock Gauze Delivery Tube Bunsen Burner Beaker Matches/Lighter Potato Hydrogen Peroxide Solution (20%) Water Lead Nitrate The skin of the potato was removed using a scalpel and then cut into 1cm², using a ruler to measure the size of each cube, four cubes are required for each experiment, and therefore at least 36 cubes are required for the full experiment to take place. Fill a beaker half way with water, and place a thermometer in the water. Allow the thermometer to warm to room temperature to gather an accurate reading, and measure the temperature, using the thermometer. A measuring cylinder was used to put 10ml of Hydrogen Peroxide Solution into a
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
Investigate the Osmosis of Potato Cells in Various Salt Solutions. Introduction I have been asked to investigate the effect of changing the concentration of a solution on the movement of water into and out of potato cells. I will be able to change the input of my experiment. The input variable is the concentration of the solution.
The Effect of Water Concentration on the Mass of Potato Tissue Aim: The aim of this investigation is to discover the effect of water concentration on the mass of potato tissue, and also to investigate the movement of osmosis through potato tissue. Scientific Knowledge: When a substance such as a sugar dissolves in water, the sugar molecules attract some of the water molecules and stop them moving freely. This, in effect, reduces the concentration of water molecules.
Type of tissue- this will be controlled by using only one type of tissue, which is the potato
the same way as it does potato. I would also widen the range of sugar
Knife to cut the potato to the correct shape and size for reasons. stated in the method. Tile to not score any school surfaces. Test tubes to hold the potato and solution in. Beaker to alter solution concentration.
An Experiment to Investigate Osmosis in Plant Tissue. Aim: To conduct an investigation to compare the osmotic behavior of the osmotic animal. two types of plant tissue in varying concentrations of sucrose. solution. Then we can find the solution.
water in the potato, then the water will go out of the potato and into
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