I could use a syringe or a burette to measure the 10ml of sucrose solution, because those two apparatus are very accurate. Each section should include the answers to the following questions Lab Topic: Effects of Osmosis with Potato Cells in Sucrose Solution Introduction: Small slices of potato are placed in six concentrations of sucrose: 0. This would make the potato hypersonic. Saam Baharmand Period 5 11 October 2014 Conclusion and Evaluation of Osmosis Potato Lab Hypothesis: I believe that the O Molar M solution of sugar and distilled water will be isotonic because there is no sugar in the solution. Folding over one end of the tubing it was tied tightly with string. The iodine solution reacted with the glucose test strips Carolina Biological osmosis lab replacement kit and turned a color indicating a positive glucose reaction.
However, sugar molecules are many times larger. Ions generally require membrane proteins to get through as do larger polar molecules. Throughout osmosis, the cell could either get larger, or smaller. I think that the experiment wasn't exactly accurate because it is nearly possible to keep the potato chips surface area exactly the same which means slight differences in the rate that osmosis occurs which can cause slight differences. The osmotic pressure is defined to be the pressure required to maintain an equilibrium, with no net movement of solvent.
This was achieved through placing potato cores in different concentrations of sucrose 0. A hypertonic solution will have a higher concentration of solutes than the cell and will have a higher osmotic pressure outside the cell than inside the cell. Permeability depends on solubility, charge, or chemistry, as well as solute size. An example is ammonia diffusing throughout a room. The bag containing the 20% sucrose solution gained the least amount of weight because it had a lower concentration of sucrose. We had 5 different situations, and we put salt to make hypotonic or hypertonic solutions. It concludes the experiment, and proves my prediction.
The other evidence is likely to be valid, because as all the evidence links to the results. Then I will empty the solution from the test tube by pouring it in the sink and remove the potatoes by hand and place them one by one on the scale. Gilbertson, Beloit Memorial High School, Beloit Wisconsin. This would also make the experimental setup be impervious to humidity and its variations. Then I realised that the scales were wrong. Purpose: In this experiment that we performed we will learn about osmosis using dialysis membrane, a selectively permeable cellulose sheet that permits the passage of water but obstructs passage of larger molecules.
Introduction: Osmosis is the spontaneous net movement of solvent molecules through a partially permeable membrane into a region of higher solute concentration in the presence of water. Three dialysis tubes were prepared with 5% sucrose solution and were soaked in solutions of different concentrations. Should you drink water from the ocean? Cell biology, Cell membrane, Chemistry 1653 Words 5 Pages Introduction Osmosis is the movement of water from a region of higher concentration hypertonic to a region of lower concentration hypotonic solution through a cell membrane or other semi-permeable membrane until an equilibrium is reached. Put the magnet inside beaker and put that beaker on the hotplate of a magnetic stirrer then stir it with the strength of less than 4. To find the percentage, I multiplied that decimal by 100. So what does the data say? One of the aforementioned activities is Osmosis, or the movement of water across a selectively permeable membrane eventually establishing equilibrium on both sides of the concentration gradient Freeman 90.
Cell membrane, Chemical equilibrium, Chemistry 962 Words 7 Pages. This causes the molecules of a cell to move around and bump into each other. Diffusion is the net movement of molecules down their concentration gradient and osmosis is a specialized case of diffusion that involves the passive transport of water. I have some ideas for cleaning it up. I think this is for two reasons: 1 You have a much larger mass of potato and so you have much smaller percentage of errors in massing; 2 you don't have as many little pieces of potato dropping off and reducing the mass. The weights of the cells were recorded each interval, and then the rate of osmosis was found by calculating the corrected cumulative change in weight. Cell membrane, Chemistry, Concentration 1723 Words 5 Pages Diffusion and Osmosis Shown In Solutions Section 1: Abstract This lab, title Diffusion and Osmosis, was centered around the diffusion across a cellular membrane and how exactly materials move and diffuse in concentrations.
This liquid or hydrostatic pressure works against osmosis. The purpose of this experiment was to determine if there are any differences between the osmolalities, the no-weight-changes of osmolalities, and the water potentials of potato cores in different solutions of different solutes. You may want to take some other measurements such as circumference, volume by water displacement, etc. Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration. The weight of the purple coloured slice will be noted before and after immersion as described above.
Most polar molecules such as sugars and proteins cannot freely pass through a lipid membrane; although water molecules are polar they are small enough to pass though the membrane freely. If a cell is in a hypertonic solution, it means that the environment outside of the cell has a high concentration of solutes, compared to inside the cell. The beakers should have been covered with aluminium foils. As the setup was left for 5h for osmosis to take place, the temperature and humidity changed considerably over the day. I hope I have shaved at least 10 minutes off of your lab prep time. Instead of having a large number of weights, I combined them into one by averaging them.