Find out what type of things affect the rate of osmosis in plants for example, temperature and time.
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Biology coursework, Osmosis Aim To find out what type of things affect the rate of osmosis in plants for example, temperature and time. I will do this using a piece of potato submerged in different amounts of sugar solution and record any changes in mass. Prediction Osmosis is the movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low concentration. Therefore I predict that the potato in the highest sugar solution will have the lowest water concentration and the weakest sugar solution will have the highest water concentration. This is due to the fact that in high sugar solutions the water leaves the cells due to osmosis making the potato lighter. Background Plant cell Animal cell Osmosis: Osmosis is just a form of diffusion it means the movement of water molecules across a partially permeable membrane from a region of HIGH water concentration to a region of LOW water concentration. Osmosis makes plant cells swell up if they are surrounded by a weak solution and they become turgid. This is useful to the plant cells as it provides support.
This meaning that I should start the clock as soon as the potato is put inside the test tube, and stop the clock as soon as 20 minutes have passed. Stopping the clock, taking them out and measuring it all in less than a minute will be tricky so I will have to work as fast as possible to get the best results. And there are obviously too many sets to go through at such a fast time. Therefore, we will try our best to weigh the potatoes as quickly and as safely as we can. Getting and experimenting with the exact measurements of molars and water is vital to this task. If the volume of one solution in a test tube is higher or lower than another this will affect the pattern of results later on. I will also make sure that the potato is fully covered by the 6 different kinds of solutions. This is because, is the potato isn't covered up by the solutions, the effect of osmosis might not occur as well as it could do. Small things such as a dirty test tube, and a slightly cracked measuring cylinder could still affect the results, and therefore I will take these into account as well.
Therefore, I would be able to concentrate more on one of the sets, instead of trying to finish all of them as quickly as we can. We also could have got more people to do the experiment with us, so that I could organise the experiment better Using more types of solutions would have helped me obtain better results, and more accurate results, so that we can make sure the results are totally correct. Experimenting with one set for a longer period of time, for each set, would give me better results, because the osmosis action would reach its maximum capability, and therefore tell me how much water could be transferred for each solution. Repeating the same tasks many other times could have improved the results although this would have been time consuming. The results that I did get backed up my predictions and proved my theory. My conclusion to this experiment is that the amount of sugar solution in the water greatly affects the amount of osmosis that goes on in plants, where the higher the amount of solution the more osmosis occurs. This would affect the plant as it gives it more turgidity and helps to stabilise it.
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