In this lab we will look at how molecules move across the membrane of a cell . Osmosis is the movement of water across a cell membrane.In osmosis the cell membrane is selectively permeable,which allows for the membrane to control what types of substances that passes through.Transportation can either be passive or active.Passive transport does not require the use of added energy where as active transport requires the cell to use energy.
Diffusion is the simplest form of passive transport. Using its own energy molecule will move from areas of higher solute concentrations to areas of lower concentrations until a balance is reached. Osmosis is also a form of passive transport.Osmosis occurs when water molecules diffuse across the cell membrane from an area of higher solute concentration to an area of lower solute concentration.
There are three relative concentrations of solutions. Hypertonic solutions yield a higher concentration than that of the cell.Hypotonic solutions have a lower concentration and isotonic solution has an equal concentration. Method:
The eggs were soaked in vinegar for 48 hours. At the end of this period the eggs are dried off and mass is recorded. The eggs are then placed in distilled water. They are removed and the mass recorded. Lastly the eggs are put into corn syrup and again removed and the mass recorded.
The egg in the vinegar got bigger, as the fluid moved into the egg, and the fluid level went down. This is an example of a hypertonic solution. In the distilled water the egg got slightly larger, but not as much as in the vinegar, as only a small amount of water moved into the egg; a more isotonic environment. After being in the syrup, the egg became smaller as the water moved out of the egg and into the syrup molecules. This is a hypotonic environment.
This experiment demonstrates the process of osmosis because when the egg is placed in the water, it gets slightly larger due to the different...
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