The human cell consists of three parts; the plasma membrane, the cytoplasm, and the nucleus. The plasma membrane is the outer boundary of the cell, it separates two major fluid compartments- the intracellular fluid and the extracellular fluid, and plays a key role in cell transport. Cell transport is the movement of materials across a selectively permeable membrane, and this process can occur in two ways; passive transport and active transport. Passive transport allows substances to cross the membrane without any use of energy, and this includes simple diffusion, facilitated diffusion, filtration, and osmosis. Active transport however, requires the use of ATP, or energy, to move across the membrane. Diffusion is the movement of …show more content…
When a cell is submerged in water, the water molecules pass through the cell membrane from an area of low solute concentration to high solute concentration. For example, if the cell is submerged in saltwater, water molecules move out of the cell. If a cell is submerged in freshwater, water molecules move into the cell. When the membrane has a volume of pure water on both sides, water molecules pass in and out in each direction at the same rate. There is no net flow of water through the membrane (Nelson 2013). The purpose of this experiment was to obtain a better understanding of how cell transport works and why it is important, and after doing this experiment, students should understand and be able to explain the differences between hypertonic, hypotonic, and isotonic solutions. The experiment aims to show how the permeability of a membrane affects the diffusion of different types of molecules, and what molecules diffuse first, fastest, and the reason. Among the experiments, four different molecules were used to explore and determine the factors that contribute to cell transport, including potassium permanganate, methylene blue, sucrose, and water. Prior to performing the experiment, the following