* Table of Contents
I. Abstract 3
II. Introduction 4
III. Materials and Methods 9
IV. Results 15
V. Discussion 18
VI. Works Cited 23
*
Abstract
This lab focuses on the understanding of osmosis and diffusion in a practical sense. It allows the conductor to see what factors affect diffusion and osmosis. This report was written to explain and present the results gathered in a precise and organized manner. This experiment was divided into two parts. The first part concentrated on the placing potato cylinders in different sucrose concentrations for a period of time. This part was conducted to see if the potato cylinders would gain weight or lose weight because of osmosis. The second part was conducted to see if a dialysis bag, filled with sodium sulfate and starch solution and placed in an albumin/glucose solution, would contain albumin/glucose from the outside or the albumin/glucose solution would contain any sodium sulfate/starch from the inside. The first part of this experiment there is a relationship between the amount of sucrose concentration and final mass. As the sucrose concentration increased the mass of the potatoes decreased. This is a result of the sucrose molecules not being small enough to pass into the membrane of the potato cylinders, but the water was able to change to a different concentration gradient. As the sucrose amount increased the free water molecules decreased, which as a result did not allow the water molecules to enter the potato cylinders. On the contrary, no diffusion of solutes occurred in part two of this experiment. Osmosis, on the other hand, did occur. Water moved into the dialysis bag, thus increasing the bag’s weight. Diffusion did not occur because of the size of the pores in the dialysis bag. The solute molecules were too
Cited: 1.Carmichael, J. (n.d.). (No Title). Laboratory #4 - DIFFUSION & OSMOSIS. Retrieved March 30, 2011, from www.und.nodak.edu/dept/jcarmich/101lab/lab4/lab4.html 2. Keith, Edward O. "Experiment 4." Lab Experiments for Introductory Biology. Kendall Hunt Pub, 2010. 41-46. Print. 3. Sinclair, K. (n.d.). BioAP- Ch7 Collaboration 2010. BioAP. Retrieved March 28, 2011, from bioap.wikispaces.com/Ch+7+Collaboration+2010 4. Lyman-Buttler, A. (n.d.). Picasa Web Albums. Picasa. Retrieved March 31, 2011, from picasaweb.google.com/lh/photo/2jQS_8D6k0wF1n-hTihj0Q