Osmosis Investigation
Aim
Investigate the movement of osmosis through a selectively permeable membrane, in this case potato.
Introduction
Osmosis is the movement of water through a semi permeable membrane, separating solutions of different concentrations. The water passes from a region of high concentration to a region of low concentration, until the two concentrations are equal in concentrations of water.
Many cell membranes behave as semi permeable membranes, and osmosis is a vital mechanism in the transport of fluids in living organisms, for example, in the transport of water from the soil to the roots in plants.
If a cell is in contact with a solution of lower water concentration than its own contents, then water leaves the cell by osmosis, through the cell membrane. Water is lost first from the cytoplasm, then the vacuole through the tonoplast. The living contents of the cell contracts and eventually pulls away from the cell wall and shrinks, this is known as Plasmolysis.
If you put a plant cell in water, water enters by Osmosis, and then swells up. However, the cell will not burst. This is due to the fact that the cell walls are made from cellulose, which is extremely strong. Eventually, the cell stops swelling, and when this point is reached, we say the cell is turgid. This is important, because it makes plant stems strong and upright.
Hypothesis
I predict, that as concentration increases, the weight and length of the potato chip will decrease. My reasoning behind this, is that the higher the concentration of glucose in a solution, the lower the concentration of water. When the potato chip is put into the solution, it will, by osmosis lose some of its water, and the water will diffuse into the solution of glucose, causing the potato chip to lose water, thus decreasing in weight and length.
Aim
Investigate the movement of osmosis through a selectively permeable membrane, in this case potato.
Introduction
Osmosis is the movement of water through a semi permeable membrane, separating solutions of different concentrations. The water passes from a region of high concentration to a region of low concentration, until the two concentrations are equal in concentrations of water.
Many cell membranes behave as semi permeable membranes, and osmosis is a vital mechanism in the transport of fluids in living organisms, for example, in the transport of water from the soil to the roots in plants.
If a cell is in contact with a solution of lower water concentration than its own contents, then water leaves the cell by osmosis, through the cell membrane. Water is lost first from the cytoplasm, then the vacuole through the tonoplast. The living contents of the cell contracts and eventually pulls away from the cell wall and shrinks, this is known as Plasmolysis.
If you put a plant cell in water, water enters by Osmosis, and then swells up. However, the cell will not burst. This is due to the fact that the cell walls are made from cellulose, which is extremely strong. Eventually, the cell stops swelling, and when this point is reached, we say the cell is turgid. This is important, because it makes plant stems strong and upright.
Hypothesis
I predict, that as concentration increases, the weight and length of the potato chip will decrease. My reasoning behind this, is that the higher the concentration of glucose in a solution, the lower the concentration of water. When the potato chip is put into the solution, it will, by osmosis lose some of its water, and the water will diffuse into the solution of glucose, causing the potato chip to lose water, thus decreasing in weight and length.
