Diffusion and Osmosis Essay

Diffusion and osmosis are essential in organic course of. Diffusion is the motion of molecules or ions from a area of their excessive focus to a area of their low focus. Osmosis is the diffusion of water molecules throughout a semipermeable membrane. To achieve a greater understanding of diffusion and osmosis, we look at a number of experiments to point out diffusion and osmosis in animal cell, plant cell and artificial cell. In our first experiment, we weight a decalcified hen egg and place 10% NaCl focus.

At each fifteen minutes intervals, we weight the egg and report that the burden decreases. In our second experiment, we use three slices of aquatic plant Elodea and add pond water one leaf, distilled water for the second and 20% NaCl for the third, then observe the cells of every leaf with a compound microscope.

Beneath microscope, chloroplasts (inexperienced organelles) in Elodea are inclined to sure to the cell wall in pond water, unfold all around the cell in distilled water, draw back from cell wall in 20% NaCl.

In our final experiment, we use a dialysis bag that incorporates 30% glucose and starch resolution then place right into a beaker of water and iodine resolution. We then take away the bag out of the beaker, and use two check tube which label BAG, BEAKER to carry out a Benedict’s check. We place resolution within the bag within the BAG tube, and resolution within the beaker within the BEAKER tube and add a drop of Benedict’s reagent to every tube, then warmth every check tube and observe a colour change in every tube. These experiments present that motion of water of hen egg cell and Elodea cell is “osmosis” and motion of molecules in dialysis bag and beaker is “diffusion”.


Diffusion is concerned in lots of organic processes occurring in single-celled to complicated organism (cite this). It's a half in life that we have to know and perceive the way it works. Diffusion is the method by which molecules transfer from an space of excessive focus to an space of low focus (cite this). A department of diffusion course of is osmosis, which is the motion of water throughout a membrane which is selectively permeable (cite this). We're going to be taught and get extra details about diffusion osmosis by carry out three experiments. We place a shell-less hen egg in salt resolution. We predict that water within the egg will transfer out the cell as a result of it is a hypertonic resolution, a better focus of osmotically energetic substance than the answer on the opposite facet of membrane.

Subsequent, we're going have three slices of Elodea in every completely different resolution: hypotonic, isotonic, hypertonic then we observe these reactions within the microscope. We predict that one can have chloroplasts (inexperienced organelles) sure to cell wall in hypotonic, one can have chloroplasts transfer within the cytoplasm, one can have cell wall stay intact and chloroplasts transfer away from cell wall. Third, we’re going to make use of a dialysis bag incorporates starch and glucose and place in water and iodine resolution. After a Benedict check, we predict that there shall be colour change in these options. These experiments are simple to carry out they usually additionally give folks sufficient data to realize higher ideas of how diffusion works in animal cell, plant cell, and artificial cell.


First, we carried out an experiment to point out osmosis in animal cell. Our supplies on this experiment had been a decalcified egg, a 350mL beaker, 10% of NaCl resolution, a triple beam steadiness, and a timer. We used the triple beam steadiness to weigh the egg. The load of the egg was 77.3g presently. Subsequent, we positioned the egg within the beaker that was full of 250mL of 10% NaCl. We waited about fifteen minutes after which take away the egg out of the beaker. We dried off the water from the egg and positioned the egg on the triple beam steadiness. The load of the egg after fifteen minutes was 76.6g. We then positioned the egg again within the beaker and repeated these steps each fifteen minutes intervals. At thirty minutes, the egg’s weight was 76.3g. At forty-five minutes, the burden was 76.2g. At sixty minutes, the burden was 76.1g. We recorded the info and calculated the % change in egg weight through the use of the burden at the moment minus the earlier weight all around the earlier time and all multiply to at least one hundred. We then graphed our information to point out % modifications in weight of the egg.

Subsequent, we carried out one other experiment to point out osmosis in a plant cell. We used leaf of the aquatic plant Elodea, pond water, distilled water, 20% NaCl resolution, a compound microscope, a pair of forceps. First, we reduce three small items from Elodea plant with forceps. We then fastidiously positioned each bit onto the microscope slide glass. We added a small drop of pond water to at least one piece and labeled it “pond water”. We added a small drop of distilled water to a different piece and labeled it “distilled water”. Final we added 20% NaCl to the final piece and labeled it “20% NaCl”. We waited for ten minutes after which we noticed the cells of every piece of leaf beneath the microscope. We then sketched the cells of every piece as seen within the microscope. In our final experiment of diffusion of artificial cell, we used a 30-cm strip of moist dialysis tubing, a string, 30 % glucose resolution, starch resolution, iodine resolution, Benedict’s reagent, scorching plate, 500-mL beaker one-third full of water, dealt with check tube holder, three normal check tubes, disposable switch pipettes, two of 400-mL beakers to carry dialysis bag.

First, we soaked the dialysis tubing in water and closed one finish with a string, and let the opposite finish open. Then we added 4 pipettesful of 30% glucose into the bag and 4 pipettesful of starch resolution to the glucose within the bag. We gently combined the contents and noticed the colour within the bag. Subsequent, we add 300mL of water to 500mL beaker. We put some drops of iodine resolution within the water and it was a brown colour. After that, we positioned the dialysis bag into the beaker and waited for thirty minutes. After thirty minutes, we moved the bag and let it stand in a dry beaker. We then recorded the info. Subsequent, we used two check tube which labeled “BEAKER” and “BAG” for the Benedict’s check. We put two pipettesful of the bag resolution within the BAG tube and two pipettesful of the beaker resolution within the BEAKER tube. We added a drop of benedict’s reagent to every tube and warmth them up in scorching water for 3 minutes. After three minutes, we noticed the colour change and recorded our information.


In our first experiment with decalcified egg in 10% NaCl, we discover that the burden of the shell-less egg decreases after each fifteen minutes time interval. At time zero, the egg has 77.3g however after fifteen minutes, the egg has 76.6, a -Zero.9% change in weight. At thirty minutes, the egg has 76.3g, a -Zero.four% change in weight. At forty-five minutes, the egg has 76.2g, a -Zero.1% change in weight. At sixty minutes, the egg has 76.1g, a -Zero.1% change in weight.

In our second experiment with Elodea plant, we discover that chloroplasts(inexperienced organelles) of Elodea cell in pond water strikes near cell wall. In distilled water, we discover that chloroplasts (inexperienced organelles) of Elodea cell transfer freely by way of out within the cytoplasm however block by cell wall. We additionally discover that chloroplasts (inexperienced organelles) of Elodea cell of in 20% NaCl transferring away from the cell wall and kind tightly within the central of cytoplasm. In our final experiment with dialysis tubing, we observe some colour change. The bag resolution, which incorporates glucose and starch, has a clear unique colour, turns to clear with some black dots as closing colour. After utilizing the Benedict’s reagent, the tube which incorporates the bag resolution turns into an orange colour.