Name: Miranda Andrews Class: BIO 480 Lab Report 1: Osmosis Due: February 22, 2017 The Membrane Permeability of Potato Cells when placed in a Sucrose Solution in the Presence and Absence of Silver Nitrate Abstract: Osmosis is the diffusion of solutes and water across a concentration gradient through channels, specifically aquaporins, to reach an equilibrium. This experiment was conducted to use potato cells and Elodea canadensis plant cells placed in various concentrations of sucrose solutions to demonstrate the process of osmosis. The experiment was also used to demonstrate the inhibitory effects that silver nitrate has on the aquaporin channels of the cell membrane by adding silver nitrate to half of the potato cell and plant leaf solutions. The potatoes …show more content…
Silver nitrate is used to inhibit the aquaporin proteins found in the membrane of the cell from allowing water to enter and leave the cell. The six transmembrane helices of the aquaporin are what allow water molecules to enter and leave the cell based on the osmotic gradient of the cell and the solution (1). Plants need aquaporins to control the water they store in different compartments (4). An osmotic gradient is the gradient where solutes and water will move through a semipermeable membrane from a low concentration to a higher concentration; this is osmosis (2). Solutes are the molecules within a solution or cell that want to have an equal amount of themselves on both sides of the gradient (3). When a cell is said to be hypotonic, there are less solutes inside of the cell than in the solution. When a cell is said to be hypertonic, there are more solutes inside of the cell than in the solution. When a cell becomes isotonic, the gradient has an equal number of solutes in the cell and in the solution