In this experiment we took dialysis bags, filled them with various sucrose solutions and placed them in water for a period of approximately 90 minutes to observe osmosis in each bag and the tonicity of each environment in which the bags were located. We also took pieces of potatoes and immersed them in various sucrose solutions to determine the ideal tonic state of the plants and the osmosis that occurred over a period of time. The final result of the first exercise was that the 0.8 M sucrose solution gained more mass and was hypertonic compared to the environment. The overall results for exercise 2 were that the 1.0 M sucrose solution lost the most mass and was hypotonic in its environment. Introduction In this lab we tested osmosis through a semi-permeable membrane using dialysis bags (SCC Science Division, 2014). We also observed osmosis in living potato cells. When water is moved through a semipermeable membrane it is called osmosis. Passive transport occurs when molecules move with the concentration gradient across the membrane without using cellular energy. Osmosis and diffusion are examples of passive transport. There is also active transport that occurs when molecules move against the concentration gradient and use energy in the form of ATP (Urry, Cain, Wasserman, Minorsky, Jackson, & Reece, 2014). There are three types of conditions affecting osmosis that will be found in this experiment: isotonic, hypertonic, and hypotonic solutions. Isotonic is when the concentration of a solute is identical outside and inside the cell. Hypertonic is when the solute concentration is greater outside the cell than inside the cell. Hypotonia is when the concentration of a solute is lower than that of the solutions outside the center of the paper......again we would try to make sure that one of the potato pieces was in a completely isotonic environment (SCC , Science Division, 2014). ReferencesUrry, L., Cain, Wasserman, Minorsky, Jackson, and Reece. (2014). Membrane transport and cell signaling. In Campbell biology at the center (pp. 94-102). Boston: Pearson.Diffusion. (2000, August 1). Retrieved October 15, 2014, from http://hyperphysics.phy-astr.gsu.edu/hbase/cinetica/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 Regulation of Cell Volume. Available from: http://www.ncbi.nlm.nih.gov/books/NBK21739/