Diffusion and Osmosis Lab Report
Hands On Approach to Diffusion and Osmosis
Abstract A. Plant and Animal Cell Diffusion and Osmosis
In this experiment we observed carmine powder to better understand the concept of Brownian motion and the role of molecular movement in diffusion. The particles continuously moved in a completely random fashion, and the smaller particles moved with more speed than the larger particles. B. Potato Core Experiment
In this experiment we estimated the osmolarity of potato tuber tissue by submersing different potato cores into sucrose solutions of 0.0-0.6M, and weighing the potato. We concluded that the osmolarity of the potato was about 0.4M since the weight of the potato did not change after it was incubated in the solution with 0.4M. We also found that the potato was hypertonic to sucrose solutions of 0.0-0.3M and hypotonic to 0.5-0.6M.
C. Dialysis Tubing Experiment
We tested the permeability of the dialysis tubing to glucose, starch, and iodine. Initially, glucose and starch were placed into the bag, and iodine outside of the bag in the beaker. We used the iodine test for the presence of starch which proved positive inside of the bag, and Benedict’s reagent for glucose which was positive outside of the bag. We therefore concluded that only small molecules like glucose and iodine can permeate through the bag, starch is too large.
Introduction
This lab has several key objectives. First, to learn about diffusion and osmosis, and the different factors that affect the rate at which these processes take place. In order for cells to maintain a stable state, they must be able to regulate the particles that move through the cytoplasm, and across its membranes. Diffusion and osmosis are the two physical processes that insure these things take place for the cells to operate smoothly. Second, to gain a better understanding of the role of selectively permeable membranes in osmosis, and to learn about the significance of hypotonic, isotonic, or
Abstract A. Plant and Animal Cell Diffusion and Osmosis
In this experiment we observed carmine powder to better understand the concept of Brownian motion and the role of molecular movement in diffusion. The particles continuously moved in a completely random fashion, and the smaller particles moved with more speed than the larger particles. B. Potato Core Experiment
In this experiment we estimated the osmolarity of potato tuber tissue by submersing different potato cores into sucrose solutions of 0.0-0.6M, and weighing the potato. We concluded that the osmolarity of the potato was about 0.4M since the weight of the potato did not change after it was incubated in the solution with 0.4M. We also found that the potato was hypertonic to sucrose solutions of 0.0-0.3M and hypotonic to 0.5-0.6M.
C. Dialysis Tubing Experiment
We tested the permeability of the dialysis tubing to glucose, starch, and iodine. Initially, glucose and starch were placed into the bag, and iodine outside of the bag in the beaker. We used the iodine test for the presence of starch which proved positive inside of the bag, and Benedict’s reagent for glucose which was positive outside of the bag. We therefore concluded that only small molecules like glucose and iodine can permeate through the bag, starch is too large.
Introduction
This lab has several key objectives. First, to learn about diffusion and osmosis, and the different factors that affect the rate at which these processes take place. In order for cells to maintain a stable state, they must be able to regulate the particles that move through the cytoplasm, and across its membranes. Diffusion and osmosis are the two physical processes that insure these things take place for the cells to operate smoothly. Second, to gain a better understanding of the role of selectively permeable membranes in osmosis, and to learn about the significance of hypotonic, isotonic, or
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