Lab Report Osmosis and Diffusion

Lab Report: Osmosis and Diffusion Abstract The main significance for the study was to see the process of osmosis and diffusion through an egg cell. The hypothesis tested was that if the egg was placed in a solute with a higher concentration of sucrose rather than a lower concentration, the egg would decrease in weight through the process of osmosis and diffusion. The general results were that the eggs that sat in the lower sucrose concentration gained weight while the eggs in that sat in the higher sucrose concentration lost weight, accepting the previously stated hypothesis. Introduction Osmosis is the movement of water molecules from a high concentrated region of water to a low concentrated region of water across a semipermeable membrane, however, diffusion is the movement of molecules or ions from high concentration region to low concentration region until equilibrium is acquired (Differences Between Osmosis and Diffusion). This theory can be proven by both of these studies Osmosis and Diffusion Conceptual Assessment and Water recovery by forward (direct) osmosis processes. Throughout the first study “Osmosis and Diffusion Conceptual Assessment”, the researchers proved that although the process of osmosis and diffusion is still elusive the main theory, as stated above, is still true. In the second article the researchers tested that water, salt, and ethanol diffusion through membranes for water recovery by direct osmosis processes proves the theory of osmosis and diffusion. Based on both articles the conclusion of membranes are selectively permeable which means that only certain materials are able to pass through. Selective permeability has its limits, because water can move but some solutes cannot, survival of a cell often depends on the water content of the liquid the cell is bathed in. In an experiment done with the study of the selectively permeable cell membrane of an egg, the theory of the process of osmosis and diffusion is proven. In this experiment the researchers hypothesised that if the egg is placed in a solute with a higher concentration of sucrose rather than a lower concentration the egg will decrease in weight because of the process of osmosis and diffusion. Materials and Methods The materials required in the experiment was four eggs soaked in vinegar, so that only the membrane was shown, and four plastic containers, filled with varying concentrations of sucrose solution from the lab instructor. The researchers filled one container with 0% sucrose solution, one container with 10% sucrose solution, one container with 20% sucrose solution, and one container with 30% sucrose solution. Along with these materials the researchers also required a few paper towels to dry off the eggs before weighing them and a scale. The experiment was carried out by the researchers placing the eggs in the appropriate solutions where they sat for 20 minutes. Once the 20 minutes were up the eggs were weighed on a zeroed out scale and the researchers recorded the difference between the starting weight and the new recorded weight of each egg. This process was repeated three more times, (40 minutes, 60 minutes, and 80 minutes). Results The results of the 0% sucrose solution and the 10% sucrose solution show that the eggs increased in weight. For the 0% sucrose solution the egg increased its weight by a total of 4.23 grams after the final 80 minute interval. The 10% sucrose solution showed the egg increased its weight by a total of 1.56 grams after the final 80 minute interval. As for the 20% and 30% sucrose solutions the results show that the eggs decreased in weight over the four 20 minute interval. For the 20% sucrose solution the egg decreased in weight by a total of 0.22 grams over the final 80 minute interval. The 30% sucrose solution showed that the egg decreased by a total of 2.18 grams. For the 0% and 10% sucrose solutions the results showed a steady increase trend after each 20 minute interval as can be viewed in Figure 1. As for the 20% and 30% sucrose solutions the results showed a steady decrease trend after each repeated 20 minute interval as can be viewed in Figure 1. See table 4.3: Change in weight (grams) of eggs for each 20 - minute interval See graph (figure 1): Changes in Weight of Eggs Through Osmosis and Diffusion Discussion The 0% and 10% sucrose solutions caused the eggs to gain weight while the 20% and 30% sucrose solutions caused the eggs to lose weight. Figure 1 shows the change in weight (grams) of the eggs every 20 minutes, while each egg was in a different percentage of solution. Based on the results the previously stated hypothesis is accepted. Along with the accepted hypothesis the experiment had no anomalous results. After this experiment was completed the researcher asked what osmosis and diffusion looks like with a human cell and how the findings from this experiment would possibly help with discovering of those answers.