Investigate Osmosis :: GCSE Biology Osmosis Coursework

Investigate OsmosisAimTo investigate osmosis. The student is going to square off what happensto the weight of a potato when it is seatd into different solutionsof sodium chlorides and water.Prediction The student predicts that potato placed in distilled water go away undergo a gain in weight and potato placed in salt solution will drop away weight. Potato placed in mixed assiduity will have no changein its weight. This prediction has been made using scientificknowledge of the special type of diffusion known as osmosis. Inosmosis, each individual cell is surrounded by a cell membrane. Thecell membrane allows small molecules to pass through it, but not largeones.Osmosis is the movement of water molecules from an area of high slow-wittedness (weak solution) to an area of low water assiduousness(strong solution) through a partially permeable membrane. body of water moves in both directions to try and make the submergencesinside and outside of the cell even. If there is more movement oneway, it is said that there is a nett movement of water into the areawhere there is less water.If the potato is placed into distilled water, the concentration ofwater outside of the cell will be greater than the concentration ofwater inside the cell. There will be a net movement of water from thearea of high concentration to the area of low concentration and as aresult of this the cell will contain more water, it will become turgidand weigh more than it did when it had a smaller concentration ofwater.If the potato is placed into a salt solution the concentration ofwater will be greater inside the cell than outside, osmosis will takeplace and the water will once again move from the area of highconcentration (inside the cell) to the area of low concentration(outside the cell). This will cause the potato to lose weight as itloses its water.If the potato is placed in a mixed solution then the concentrationsinside and outside of the cell should be equal, the water moleculeswill move by osmosis but the concentrations will remain equal.Apparatus- 125ml of 1ml sodium chloride solution.- 125ml distilled water.- 15 cylinders of potato each weighing 5.3g.- 15 beakers (150ml).- 2 measuring cylinders (50ml)- 2 potato borers (one large one small).- 1 set of digital weighing scales.- 1 calculator- 1 small scalpel- 1 stop clock mode The student will use a potato borer to cut out 15 cylinders ofpotato to the same size and weigh them, the weights will be recordedin the table of results (each piece of potato should be the same