During our biology lab we learned all about cells, and to further our understanding we even conducted an experiment with an artificial cell. To start the lesson, we learned the difference between diffusion and osmosis, how concentration gradients affect both. Also how the cell membrane works, how tonicity affects plant and animal cells differently, how dialysis tubing works, and how it acts like a living cell. By the end of the lesson we understood that osmosis is a phenomenon that all cells have to deal with (Thorpe, 2015). To better understand how osmosis works we set up an experiment, and recorded our results. Osmosis is the passive movement of water from an area of …show more content…
Four strips of dialysis tubing were soaked in water until softened. They were opened on one end and closed on the opposite end with a clamp. Each of the four cells were prepared with 10 mL of a different solution; one containing water, one containing 10% sucrose, one containing 20% sucrose, and one containing 40% sucrose. Before closing the open end of the cell with a clamp, fingers were used to push the excess air out. Four Beakers were labeled and filled with enough water to cover each cell. Making sure to blot the cells dry, each one was weighed and their mass was recorded in the first column of Table Three: Artificial cell results. The cells were simultaneously placed in the beakers and a timer was set for ten minutes. After the timer reached ten minutes, the cells were taken out of the beakers, blotted dry, and weighed. After the mass of all four cells was recorded, the cells were placed back into their original beakers. This process was repeated until the cells had been weighed and recorded for a total of seventy minutes. After the last of the data was recorded, the contents of the cells were emptied down the drain and the dialysis tubing was tossed in the trash …show more content…
The rate of Osmosis in the different artificial cells.
We measured the rate of osmosis by finding the slope of the lines from figure 1. What we found is that the lowest concentration has the slowest rate of osmosis, while the highest concentration of solute has the fastest rate of osmosis.
Discussion-
The results collected from this experiment supported our hypothesis. We predicted that as the percent of sucrose increased, the rate at which the cells gained weight would also increase. You can gather this information from table 1. Bag number two held 10% sucrose, and the rate of osmosis was 0.0307g/min. Bag number four held the 40% sucrose, and the rate of osmosis was 0.0991g/min.
We were all interested in the dialysis tubing. We didn’t even know what it was until we soaked it in water. The whole idea of plastic mimicking the cell membrane didn’t seem convincing, but in the article “Red Onions, Elodea, or decalcified chicken eggs? Selecting & Sequencing representations for Teaching Diffusion & Osmosis” it also mentions dialysis tubing. The article says that dialysis tubing makes excellent macroscopic representations for both diffusion and osmosis (Lankford & Friedrichsen, 2012). It also says that tubing is semipermeable just like real cell membranes (Lankford & Friedrichsen,