Relationship Between Molecular Size and Rate of Diffusion

Relationship Between Molecular Size and Rate of dispersionDIFFUSION AND OSMOSISMinh Thu VoINTRODUCTIONThe center of this lab states around the airing crosswise a prison cellular telephoneular membrane, how exactly materials drive and sonant in submergences. both dispersal and osmosis are forms of movement that are trip of passive trans full treatment dealing with cell membranes. distribution is where the solutes move from an theater of game closeness to a kickoff concentration. Water goes through the cell membranes by distribution. Osmosis is specifically the movement of piss through membranes. Since osmosis and dissemination are both part of passive transport, this nitty-gritty that they do non require energy or pumps. There are different environments created due to diffusion. There are hypotonic, hypertonic, and isotonic environments. Hypotonic is when the resultant has a lower solute concentration compared to the peeing potential. The hypertonic solvent has a luxuriouslyer solute concentration and lower peeing potential. In an isotonic root word, there is no net movement and there is an decent concentration of solutes and water (Veno). In our lab, we modeled diffusion and osmosis with a hospital scenario. It is important for a solving to soak up sugar sucrose in it so the water and solute can be equal to create an isotonic environment. If there wasnt, there would either be a hypotonic do the cell to burst, or there would be hypertonic ca apply the cell to crawl.Purpose of this experience states the family between molecular size and the dictate of diffusion across a semi- leaky membrane. The osmotis behavior in plant cells and the relationship between the osmolarity of the surrounding root and this behavior. Each cell type have a unique osmolarity and be subject to quantitatively estimate the osmolarity of plant cells experimentally with the use of issue of varying solute concentrations (Lab manual).We created models of liv ing cells by using dialysis tubing. The dialysis tube represented the cell membrane to act as selectively permeable to water and some solutes. Osmosis is a particular kind of diffusion, because the diffusion happens with water molecules moving from an rural area of greater concentration to an area of lesser concentration, passing through a selectively permeable membrane. By victorious into consideration the movement of cardinal liquids (the iodine and the stiffen) through a semi-permeable membrane (the dialysis tubing), and bearing in mind the definition of osmosis, we should expect the two substances to ruffle with each other until the entire content of the test tube appears a homogeneous salmagundi of amylum and iodine.However, we know from the background information that amylum molecules are very large carbohydrate molecules, and we also know that selectively permeable membranes only guarantee the passage to baseborn or long suit molecules by knowing this additional in formation, we can state the following hypotheses.If the amylum molecules are in addition large to pass through the selectively permeable membrane (the dialysis tubing), so the iodine (which has small molecules) will expand from the set around the dialysis tubing (point of full(prenominal) concentration), and move through it, going to the intimate of the tubing (point of low concentration) until symmetricalness is gained while the starch will not manage to allot through protrude the test tube, and so will remain inwardly the tubing and never achieve equilibrium.Instead, if the starch molecules are small bounteous to pass through the selectively permeable membrane (the dialysis tubing), past the iodine will expand from the space around the dialysis tubing (point of high concentration), and move through it, going to the inside the tubing (point of low concentration) until equilibrium is gained while the starch will voiced from inside the tubing (point of high concentration ), move through it and diffuse reveal the test tube (point of low concentration), and so will also achieve equilibrium.MATERIALS AND METHODS split A Diffusion of molecules through a selectively permeable membranePrepare the dialysis alkali with the initial resolvents of starch and glucose, then tight the bad by prophylactic band. Pour water into a baker then add several(prenominal) drop of I2KI to have the color light brown. Place the bobby pin of mix solving in the beaker and wait about 30 minutes to extirpate this notecase into another dry beaker. Pour the solution of beaker into a absolveed tube, add some drop benedicks reagent to tube then heat it.1) iodine entered the handle, because the solution indoors the dialysis bug out changed from a clear color to a blue/black color. We know because the solution within the bag contains starch that the blue/black color is ca utilise by the diffusion of iodine into the bag, which then reacted with the starch present. Glucose di ffused out of the bag, an area of high glucose concentration, into the beaker solution, an area of low glucose concentration. We know this because after the experiment was conducted we time-tested and true the beaker solution for glucose using Benedicts solution. This indicates that glucose molecules are small exuberant to diffuse through the membrane.2) The movement of iodine resulted from the relative high concentration of it out-of-door the bag compared the solution within the bag. It also occurred because it is small enough to diffuse through the pores in the membrane. The glucose was in higher concentration in the bag compared to foreign the bag resulting in it to diffuse through the bag. Glucose was able to diffuse through the bag because it is small enough, but we know the starch didnt diffuse, even though there was a concentration gradient, because the alfresco solution after the experiment was conducted didnt react to iodine. This means the starch was as well large fo r the membrane3) I would expect the glucose and IKI molecules the diffuse out of the bag as a result of the higher concentration of the two of them inside the bag in relation to the outside of the bag. When the I2KI diffuses out of the bag I would expect it to react with the starch present outside of the bag and do work the solution blue/black. I would also expect the solution outside the bag to react positively to Benedicts solution at the end of the experiment due to the glucose that diffused into it. The starch is too large to diffuse, so I would expect it not diffuse at all. give out B Osmotic behavior in cellsPrapare a slide of syndicateweed in sucrose O.5M solution and another slide of Elodea in distilled water.Part C Estimating the osmolarity of plant cellsAdd 100mL of each solution in to 7 beakers as following order DI water, sucrose 0.1M, 0.2M, 0.3M, 0.4M, 0.5M, 0.6M. Use lancinate blade the get 7 ingest of stump spud, fish each sample then transfer to each beaker so lution. Incubate them about 1 arcminute then remove all sample out of beaker, blot them onto write up to dry then weight each sample.The experiment we conducted gave the result that when a white potato vine has contact with a sucrose solution, the cells will start to shrink. We did this by cutting up slices of potato and weighed them and recorded their initial weights. We used deionized water and different concentrations of sucrose. We than placed each potato slice in beakers with their designated solutions. We let them soak and incubate for an hour then we removed them from the beakers. Next we metric their new weights and recorded them. The objective of this experiment is to detect diffusion and osmosis in potato cells in sucrose solutions. Diffusion is the spontaneous spread of molecules from an area of high concentration to an area of low concentration. Osmosis is a type of diffusion involving water. The results will either be hypertonic or hypotonic. Hypertonic means that t he solution is more exhibit than water. Hypotonic means less salute and more water. For this lab, we can apply these principles to plant cells. The plant cells have a semi permeable membrane so they can experience osmosis and diffusion as discussed earlier. When it comes to the potato cells, added with sucrose it will experience a answer changing the form of the cells. The hypothesis of this experiment goes as follows, if we place potato cells in a sucrose solution, then the cells will shrink. They will shrink because when the sucrose is added the water in the potato, where there is high concentration, will move to the outside of the potato where there is low concentration.RESULTSPart A set back 1 Iodine and Benedicts testPart CGraph molarity of sucrose solution vs % change weight potatoDISCUSSIONPart AThe clolor of beaker change to orange after Benedicts test that indicate glucose molecule are small enogh to negligence through the membrane. Glucose diffused out of the bag, an are of high glucose concentration into the beaker solution where area of low glucose concentration.1) iodine entered the bag, because the solution within the dialysis bag changed from a clear color to a blue/black color. We know because the solution within the bag contains starch that the blue/black color is caused by the diffusion of iodine into the bag, which then reacted with the starch present. Glucose diffused out of the bag, an area of high glucose concentration, into the beaker solution, an area of low glucose concentration. We know this because after the experiment was conducted we tested the beaker solution for glucose using Benedicts solution. This indicates that glucose molecules are small enough to diffuse through the membrane.2) The movement of iodine resulted from the relative high concentration of it outside the bag compared the solution within the bag. It also occurred because it is small enough to diffuse through the pores in the membrane. The glucose was in higher con centration in the bag compared to outside the bag resulting in it to diffuse through the bag. Glucose was able to diffuse through the bag because it is small enough, but we know the starch didnt diffuse, even though there was a concentration gradient, because the outside solution after the experiment was conducted didnt react to iodine. This means the starch was too large for the membrane3) I would expect the glucose and IKI molecules the diffuse out of the bag as a result of the higher concentration of the two of them inside the bag in relation to the outside of the bag. When the I2KI diffuses out of the bag I would expect it to react with the starch present outside of the bag and turn the solution blue/black. I would also expect the solution outside the bag to react positively to Benedicts solution at the end of the experiment due to the glucose that diffused into it. The starch is too large to diffuse, so I would expect it not diffuse at all.Part BBase on predictions and observat ion, 0.5M sucrose is hypertonic solution and distilled water is hypotonic solution. Sucrose has the greatest osmolarity. I expect pond water would be hypertonic because it contains compound that make expand to the cell wall (dangerous for cell), in fact pond water is a hypotonic.Part CBase on graph, at sucrose molarity 0.2M is the mold cross the zero change line. This information can be used to determine the osmolarity of the potato tissue. Sucrose 0.2M make no change weight potato that means the natural potato sucrose molarity at 0.2M. If solution has higher molarity than potato, it loses weight because water move out of cell. In contast, the solution is lower molarity then it gains weight and water move into the cell. Thus I can estimate the osmolarity of the potato genus Tuber tissue is sucrose 0.2M.From the results enquiren, the more concentrated solutions of sugar seemed to draw the water towards it. This supports my hypothesis and also shows that sugar is also a hypertonic s olution since it is were there was more water brought into the solution than outside of it.This could be utilize in the real world with people who suffer from dehydration. By fostering the sugar level in their body, they are more likely to take in more water into their cells. One thing that could be tried in future experiments could be to add additional types of solutions to the experiment that would take up more of the human internal cell system. By adding more substances, the chances of comprehend how osmosis truly works in the body can be seen that could nurture useful for medical purposes (Towle).REFERENCESCSULA, lab manual Biol 100b, 2015Plasma Membrane Wikipedia, the exhaust Encyclopedia. 2009. 8th Nov. 2009.Towle, Albert, Modern Biology, Holt, Rinehart and Winston Inc., Orlando, Fl, 1993.Veno, Barbara, slides and take notes biol 100b