Osmosis Through A Semi Permeable Membrane Using Dialysis Bags

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In this experiment we took dialysis bags and filled them with various sucrose solutions and put them in water over a period of about 90 minutes to look at the osmosis in each bag and the tonicity of each environment the bags were in. We also took potato pieces and submerged them into various sucrose solutions to determine the ideal state of tonicity for plants and the osmosis that occurred over a period of time. The final results for the first exercise was that 0.8M sucrose solution gained the most mass and that it was hypertonic to its environment. The overall results for exercise 2 was that 1.0M sucrose solution lost the most amount of mass and was hypotonic to its environment.
Introduction
In this lab we tested osmosis through a semi permeable membrane using dialysis bags (SCC Science Division, 2014). We also looked at osmosis in living cells of potatoes. When water is moved through a semi permeable membrane that is called osmosis. Passive transport is when molecules move with the concentration gradient across the membrane with no cellular energy used. Osmosis and diffusion are examples of passive transport. There is also active transport which is when molecules move against the concentration gradient and uses energy in the form of ATP (Urry, Cain, Wasserman, Minorsky, Jackson, & Reece, 2014). There are three types of conditions that deal with osmosis that will be found in this experiment: isotonic, hypertonic, and hypotonic solutions. Isotonic is when the concentration of a solute is identical outside of the cell and inside of the cell. Hypertonic is when the concentration of solute is higher outside of the cell than inside of the cell. Hypotonic is when the concentration of a solute is less than the solutions outside the c...

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...again we would try to make sure that one of the potato pieces was in a completely isotonic environment (SCC, Science Division, 2014).

References
Urry, L., Cain, Wasserman, Minorsky, Jackson, & Reece. (2014). Membrane Transport and Cell
Signaling. In Campbell biology in focus (pp. 94-102). Boston: Pearson.

Diffusion. (2000, August 1). Retrieved October 15, 2014, from http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/diffus.html Surry Community College. (2014). Osmosis and diffusion Part 1. In SCC Science Division (Ed.),
Lab manual-Biology 111-General Biology I (pp. 35-37). Dobson, NC: Surry Community College.

Lodish H, Berk A, Zipursky SL, et al. Molecular Cell Biology. 4th edition. New York: W. H.
Freeman; 2000. Section 15.8, Osmosis, Water Channels, and the Regulation of Cell Volume. Available from: http://www.ncbi.nlm.nih.gov/books/NBK21739/

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