Class 5

              Today in class Mr. Quick went over and explained the diffusion and osmosis labs from last class as we drew graphs to better understand the lab. The potato is shown in the graph as hypertonic at first and the solution is hypotonic. When the line hits the x-axis, it is isotonic. Then the line shows that the potato becomes hypotonic and the solution becomes hypertonic, so the mass increased and the molarity in the solute decreased. We continued the osmosis and diffusion lab. We had permeable "cells"that contained starch and glucose. We predicted that the starch particles were too big to pass or enter the cell but that the glucose would pass through. We first added iodine to the solution and noticed the blue color  that showed an amount of starch. We put it in water for 15 minutes. When we heated the solution it turned an orange color showing that glucose had left the tubing. Then we cut up the cells into cubes, each a different size. We measured the size and volume of each cube before and after the experiment. We put them into the solution to see how much diffusion would occur and measure it. Then we put the semi permeable membrane "cell" into water with iodine in it to see if any starch would leave the cell. The cell turned black concluding that the starch had not left.