Osmosis Investigation Essay -- GCSE Biology Osmosis Coursework

Osmosis InvestigationHow dissimilar concentrations of sucrose solution effect spud tissue.AimHow do different concentrations of sucrose solution effect potatotissue.Background InformationOsmosis is the movement of water molecules though a partiallypermeable membrane from an area of uplifted water potential to an area oflow water potential.High ConcentrationLow ConcentrationThe membrane lets small water molecules pass though but not largeones.The flow continues until the concentration becomes the same on theinside as on the outside. This is called equilibrium.Molarity is a measure of concentration.PredictionI visit that the potato testament change in mass and in length. I believethis beca routine each Molarity of sucrose ordain change the potatos watercontent. This will happen because either the concentration will higherin the sucrose and lower in the Tubas or lower in the sucrose andhigher in the Tubers. Therefore water will travel in or out of thepotatoes cell though its part ial permeable membrane.Preliminary Method I will firstly get 10 test tubes and to test tube racks Then I will cut 9 pieces of potato I will hence get 3 different Concentrations of sucrose solution and add 20cm3 to each test tube Cut a 4 mm in diameter tuba to 1 cm in length straightway I will measure the length and mass Now place the pieces in Now leave this for 15 minutes Now I will measure the length and massPreliminary ResultsAfter we did the Preliminary Test we decided to use 1 cm long 4 mmdiameter tubas. We would put them in 25 cm3 sucrose solutions. I dont construct any actual results because the potato tubas shrivelled up in thefridge.Method1. I took two average sized ground potatoes and checked that they were both healthy and hard.2. Using a bar kitchen knife I peeled the potatoes and utilise a potato tuba to cut 18 equally size tubas3. Using a scalpel and ruler I cut the potato into lengths of 4mm by 10mm. I had to be very careful whilst cutting the potato as th e scalpel is exceptionally sharp. I then had 18 tubas4. taking a test tube rack I placed 18 test tubes in it and then labelled them (0.00M, 0.25M, 0.50M, 1.00M, 1.50M, 2.00M)5. Using a measuring piston chamber I measured out 25cm3. I then poured this carefully into ea... ...the water potential inside the tissue.To measure the genus Tubers I think I would use a digital measurer that goesto two decimal places for accuracy and it would go to the sameaccuracy level as the top pan balance.I would also increase the cadence molar amounts I use, such as 0.25 and0.75. one explanation for the bad results is when the potato chipswere removed from the test tubes and dried I may well have dried somepotatoes more thoroughly than others and so some would have moreexcess water, which would add to the mass. If the experiment wasrepeated I could find other way to dry the potatoes that wouldensure that all were dried in the same way for the same time. I wereto repeat the experiment I would h ave mayhap found a machine to cutthe potato as it would ensure that all potatoes would be the sameweight and dimensions. As well as the potato I could have found a moreaccurate way to measure out the solutions and to determine the molarconcentrations. Perhaps I could have used a burette. This would ensurethat I have an accurate amount of fluid in each test tube. I couldalso weigh each tuber on a more accurate scale, e.g. not to 0.00g butto 0.0000g