Osmosis is a special case of diffusion. It is when the passage of water from a dilute solution moves through a semi-permeable membrane to a more concentrated solution. Selective permeability is whether solutes can cross through a membrane freely or not at all. Plant cells and animal cells differ in that plant cells have a strong cell wall and animal cells do not have cell walls. They both can undergo osmosis and both lose water, however the cell wall of plant cells prevent the cells from bursting whereas animal cells will burst because they have no cell wall.
Methods:
Osmosis:
Obtain four, 15cm long sections of dialysis tubing that have been presoaked in RO H2O.
Create bags by folding over one end of each dialysis tube and tying that end
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Consequently the weight of the sucrose solution bags increased the greatest. The results of this experiment were what was expected and proved the hypothesis to be true because the sucrose solution was of lower concentration due to the fact it increased in weight the most. Thus, the more water moved through the semi permeable membrane compared to the others. If there was anything to change with this experiment, it would be procedurally. I would be sure to use different semi permeable membrane bags that don’t allow water to leak due to the fact that both ends were only closed with a rubber band and it was difficult to ensure the bags were tightly sealed. This could help prevent …show more content…
Specifically for the lab discussed we were to determine whether sucrose of RO H20 was of higher or lower concentration. We were able to determine permeable membranes were depending on the concentration of the solution or solvent. In this case we learned that solution and solvents of lower concentration allow for greater flow through the semi-permeable membrane, which supports the idea of diffusion. We learned that sucrose solution allowed for greater diffusion than RO H20. Also chloride ions and aluminum allowed for diffusion whereas starch and sulfate ions did not. We also learned Elodea in NaCl solution underwent a process called plasmolysis where the cells
When the cell has all the water it can take inside of it the osmosis
In life, it is critical to understand what substances can permeate the cell membrane. This is important because the substances that are able to permeate the cell membrane can be necessary for the cell to function. Likewise, it is important to have a semi-permeable membrane in the cell due to the fact that it can help guard against harmful items that want to enter the cell. In addition, it is critical to understand how water moves through the cell through osmosis because if solute concentration is unregulated, net osmosis can occur outside or inside the cell, causing issues such as plasmolysis and cytolysis. The plasma membrane of a cell can be modeled various ways, but dialysis tubing is especially helpful to model what substances will diffuse or be transported out of a cell membrane. The experiment seeks to expose what substances would be permeable to the cell membrane through the use of dialysis tubing, starch, glucose, salt, and various solute indicators. However, before analyzing which of the solutes (starch, glucose, and salt) is likely to pass through the membrane, it is critical to understand how the dialysis tubing compares to the cell membrane.
Investigation of the Concentration and the Effect of Sucrose on Osmosis in Apple and Potato Tissues
This cell membrane plays an important part in Diffusion. Cell membrane and Diffusion Diffusion is the movement of the molecules of gas or liquids from a higher concentrated region to a lower concentration through the partially permeable cell membrane along a concentraion gradient. This explanation is in the diagram shown below: [IMAGE] Turgor When a plant cell is placed in a dilute solution or a less concentrated solution then the water particles pass through the partially permeable membrane and fill the cell up with water. The cell then becomes Turgor or hard. An example of this is a strong well-watered plant.
Activity 3: Investigating Osmosis and Diffusion Through Nonliving Membranes. In this activity, through the use of dialysis sacs and varying concentrations of solutions, the movement of water and solutes will be observed through a semipermeable membrane. The gradients at which the solutes NaCl and glucose diffuse is unproportional to any other molecule, therefore they will proceed down their own gradients. However, the same is not true for water, whose concentration gradient is affected by solute ...
* In the first dialysis tube (bag A), we would insert ten mL of one
The experiment is aimed at giving a better understanding of the osmosis process and the different conditions in which osmosis occurs. INTRODUCTION When a cell membrane is said to be selectively permeable, it means that the cell membrane controls what substances pass in and out through the membrane. This characteristic of cell membranes plays a great role in passive transport. Passive transport is the movement of substances across the cell membrane without any input of energy by the cell.
molecules go in and out of the cell. There is no net movement of water
The purpose of this lab was to see firsthand the diffusion of a substance across a selectively permeable membrane. Diffusion is the movement of molecules from an area of high concentration to an area of lower concentration until both concentrations are equal, or as you could more professionally call it, equilibrium. This concept is one that we have been studying in depth currently in Biology class.
If a plant cell is places in a hypotonic solution the cell has a lower water concentration to that of the solution. Water will move into the cell by osmosis from a high water concentration outside the cell to a lower water concentration inside the cell through a selectively permeable membrane. The cell becomes turbid
the same way as it does potato. I would also widen the range of sugar
Most cell membranes are like that, being permeable to water and some solutes only. Osmosis is therefore the diffusion of water through a partially permeable membrane. The basic principles of diffusion apply here.
Now, assemble and arrange all of the needed supplies so that they are easily accessible. Connect the IV tubing to the solution bag and allow the fluid in the bag to run through the entire length of the tubing, also known as priming the tubing. When this is done, clamp the tubing closed. You will then need to tear several pieces of tape, six to eight inche...
Osmosis is the passage of water molecules from a weaker solution to a stronger solution through a partially permeable membrane. A partially permeable membrane only allows small molecules to pass through, so the larger molecules remain in the solution they originated in. Solute molecule [IMAGE] [IMAGE] Water molecule [IMAGE] The water molecules move into the more concentrated solution. When water enters a plant cell it swells up. The water pushes against the cell wall and the cell eventually contains all that it can hold.
== = 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.