Cell Simulation Prac
Aim: To place cells in substances in 12-millimetre dialysis tube with
the intentions of osmosis occurring and figuring out how much
weight has been added (in grams) during osmosis.
Apparatus: You will need:
 6x 250ml beakers
 Starch
 Salt
 Water
 Sucrose
 Iodine
 Onion
 Bunsen Burner
 Tripod
 Heat mat
 Gauze mat
 12mm dialysis tubing
 15x rubber bands (this is including spares)
 Digital scales
 Thistle funnel
 Bosshead
 Clamp
Method: The method used for the following experiments use the
same steps, just whilst substituting different ingredients as advised.
1. Wet 12mm dialysis tubing OVERNIGHT.
2. Next morning get out dialysis tubing and rub together to
separate.
3. When opened strap one end shut with a rubber band, very
tightly to avoid leakage.
4. Fill the tube with desired substance and tightly strap other end
shut with rubber band.
5. Then get your 250ml beaker and place the desired substance
within it. (If salt is the wanted substance, then you must place
it in water and heat for approximately 1 min 30sec with a
Bunsen burner.
6. Before placing in cell simulation be sure to dry, weigh and
record carefully with digital scales.
7. When finished place beaker out of harm’s way and leave for a
minimum of 3 hours (we left ours about 48)
8. Weigh cell again and this will determine how much matter has
entered the cell via osmosis.
Method 2: Experiment 6:
1. Close off one end of the dialysis tube with rubber band and seal
tightly.
2. Place sucrose in the cell and seal off other end, making sure it is
attached to the smaller end of the thistle funnel.
3. Place water in the beaker and place cell in, with thistle funnel
connected to retort stand, bosshead and clamp.
4. Mark the level of water and come back and leave for several
hours.
5. Record new level and difference in height of water.
Results:
Conclusion:
With the first two experiments we discovered that the weight of the
cell simulations went down, where as the other and third experiment
goes up n weight. Either way none of these have leaked or are
incorrect as the cell is simply trying to make a state of equilibrium
and is functioning in accordance to that.
1. Diffusion is the movement of particles (fluids) from a high
concentration to a low concentration, creating a state of
equilibrium, moving through a semi – permeable membrane
(cell membrane). Some example of this is when a fart’s smell
wafts from one side of a room to another and when gas is
released into a container it spreads throughout of it.
2. A semi - permeable membrane is an outlining substance of
usually a cell that allows some substances to move through it
and others not. We find a semi – permeable membrane in the
cell membrane of the cell, because it allows substances to enter
and exit through it.
3. The difference between osmosis and diffusion is that diffusion
is the movement of particles (fluids) from a high concentration
to a low concentration, creating a state of equilibrium, moving
4.
5.
6.
7.
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through a semi – permeable membrane (cell membrane). On
the other hand osmosis is when one substance travels through
a semi - permeable membrane, resulting in the two substances
diffusing.
Osmosis is important to plants because of the way in which it
can cause the plant to bulge and bulge and nearly explode due
to varying pressure levels, although the plants withstand this
pressure with the rigid cell wall normally keeping it together.
Fish on the other hand when in ocean water fish are always
drinking water to cater for the water they’re losing via osmosis,
where as fresh water fish are always urinating water to avoid
overloading with it.
Starch and sugars enter the cell via a process known as active
transport.
Starch – an odourless, tasteless white substance made up of
large, unrefined glucose cells connected by glycosidic bonds. It
is the most common carbohydrate in the human diet, with
potatoes, wheat, corn and many other substances containing it.
Sucrose – Sucrose is the organic compound most commonly
known as dissolved table sugar in water, in it’s solid form it is a
white crystalline substance, also known as, saccharose.
Glucose – Glucose is a simple monosaccharide found in all
plants. It is one of the three monosaccharaides, along with
fructose and galactose that can be absorbed directly into the
bloodstream during digestion.
Photos in order of:
1. Water cell in glucose
2. Glucose cell in water
3. Starch in iodine
4. Onion cell in dissolved salt
5. Onion Cell in water
The sixth and final experiment- using a thistle funnel mark the level of water and
see whether it rises or falls.
Above: Experiments 4 and 5 after soaking:
Observations
Experiment 4 has slightly expanded.
Experiment 5 has slightly shrivelled.