Daniel George
Department of Biology
Grand Valley State University
1 Campus Drive
Allendale, MI 49401 georged@mail.gvsu.edu Abstract The lab for this paper was conducted for the topic of osmosis, the movement of water from high to low concentration. Five artificial cells were created, each being filled with different concentrated solutions of sucrose. These artificial cells were placed in hypertonic, hypotonic, or isotonic solutions for a period of 90 min. Over time, the rate of osmosis was measured by calculating the weight of each artificial cell on given intervals (every 10 minutes). The resulting weights were recorded and the data was graphed. We then could draw conclusions on the lab.
Introduction
Diffusion and Osmosis are two concepts that go hand in hand with each other. Diffusion is simply described as the movement of a substance from a region of high concentration to a region of low concentration. In another words, the substance will move down its concentration gradient which is “the region along which the density of a chemical substance increases or decreases” (Campbell Biology pg. 132). If you understand the concept of diffusion then osmosis is a very simple process. It can be defined as the diffusion of water across a permeable membrane. Osmosis can be cellular or artificial, so even though we are creating artificial cells in this lab, it is still considered to be osmosis. During osmosis, a solvent is trying to get through a selectively permeable membrane to make the concentration of that solvent the same on both sides of the membrane. The rate of osmosis depends on the type of environment the cell is in. There are three different environments that a cell can find itself in, a hypertonic environment, a hypotonic environment, or an isotonic environment. The environment a cell is in will determine its tonicity which is “the ability of a surrounding solution to cause a cell to gain or lose
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