Investigate how temperature affects the permeability of beetroot cell membrane.
Permeability of beetroot membrane
Aim
To investigate how temperature affects the permeability of beetroot cell membrane.
Introduction
The purpose of a cell membrane is to control the transport of substances moving into and out of a cell. The membrane is an extremely thin layer (8 to 10 manometers (nm)) thick, which is partially permeable. It consists mostly of lipids and proteins. The lipids found in cell membranes belong to a class known as triglycerides, so called because they have one molecule of glycerol chemically linked to three molecules of fatty acids. The majority belong to one subgroup of triglycerides known as phospholipids.
Transport across membrane. Materials need to be transported into and out of cells in order for the cells to function efficiently. Cells need to take up nutrients and water, exchange respiratory gases, secrete enzymes and hormones and excrete metabolic waste products. This movement of molecules involves crossing the cell surface membrane and also the intracellular membranes of the endoplasmic reticulum and other organelles. These membranes are partially permeable and in order to have an understanding of how movement is achieved it is necessary to refer to the fluid-mosaic model of membrane structure. The fatty acid chains of the phospholipids molecules that make up the lipid bilayer are hydrophobic and so specific transport systems are required for water-soluble molecules to cross the membranes.
