Factors Affecting Osmosis in Potato Tissue
Introduction:
I am going to design and modify an experiment used to show osmosis in
potato chips in different concentrations of sucrose solution. I am
also going to investigate on how potato chips change in volume and
weight when placed in different concentrations of sucrose solution. I
will also conduct a preliminary experiment before my final experiment.
Aim:
To investigate the effect of different concentration of sucrose
solution on potato chips.
Hypothesis:
I would expect the potato chips to turn flaccid when they are placed
in a strong sucrose solution because the water from within the cells
will diffuse out leaving the potato flaccid. The potato chips left in
the weak sucrose solutions should turn turgid in a weak sucrose
solution, due to the water being absorbed by osmosis into the cells of
the potatoes, this will make the potato chip larger in size. I should
also be able to find some potato chips, which have neither increased
nor decreased in size because the concentration in the potato is the
same as the sucrose solution, so no mass or length would be gained or
lost.
Scientific knowledge:
Osmosis is a type of diffusion, where the molecules move from an area
of high concentration to an area of low concentration passing through
a partially permeable membrane. When distilled water or a weak sucrose
solution or a diluted sucrose solution is used, the water molecules
will pass through the semi-permeable membrane into the potato. This is
due to the fact that the water is more concentrated outside, so the
molecules in the water will move through the permeable membrane, and
in this experiment it will pass through into the potato. The potato
chip will increase in length, and weight due to osmosis. When a strong
sucrose solution or a concentrated sucrose solution is used, the water
within the potato will move out of the potato through the
semi-permeable membrane, and into the strong sugar solution, of which
Investigation of the Concentration and the Effect of Sucrose on Osmosis in Apple and Potato Tissues
Osmosis Experiment Planning Aim: The main subject that I will be planning to investigate is the effects of a concentrated sucrose solution on potato cells on the basis of the Osmosis theory. Background knowledge: The plant cell and its structure To understand osmosis in detail I will need to explain the plant cell (which is the cell included in the osmosis experiment) and its cell membrane. Below I have a diagram of a plant cell: [IMAGE] Osmosis is about the movement of particles from a higher concentrated solution to a lower concentrated solution to create an ethical balance via a partially or semi permeable cell membrane. Osmosis in simple terms is the exchange of particles between the cytoplasm inside the cell and the solution outside the cell. What makes this exhange is the partially permable cell membrane.
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.
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 water molecules move freely through the semi-permeable membrane; this is a passive process. We will do this experiment by placing potato chips in different strength solutions and checking for mass increase/decrease. Prediction I hypothesize that if we place potato chips in different strength solutions that there should be different results, some with noticeable changes in mass, the other will be nearly the same. The potatoes should gain/lose mass by the movement of water. If there is a change in mass, it is because water has entered or left the cell.
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.
When doing this experiment I was able to see the effect of different concentrations on the rate of osmosis, each was done by measuring the initial mass and length of the potato cylinder and after osmosis, the results were conducted to show that as the sucrose concentration increases the rate of osmosis also increases as I said in my hypothesis thusly making a direct decrease in mass.
This is because the water molecules passed from a high concentration in the water, to a low concentration, in the piece of potato. Therefore, the potato in higher water concentrations will have a larger mass than in higher sucrose concentrations. i.e. The potato pieces are shown to have water potential. The attached graph shows the concentration of the sucrose solution plotted against the average mean change in mass.
the same way as it does potato. I would also widen the range of sugar
This is because the water molecules pass from a low concentration to a high concentration, (in the potato chip). Therefore, the chips in low concentrations will gain mass and have a greater length height than in higher concentrations such as 1molar of sugar solution. If there is no gain or loss in height or mass then these will be the isotonic points of the potato cells. The isotonic point is where the cells are not increasing or decreasing in size and is known to be in a state of equilibrium. Apparatus: 1.
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.
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.