Introduction: • Cell membranes are vital to proper cellular function • Cell membranes consist of a lipid bilayer made up of phospholipids • Phospholipids are amphipathic molecules meaning they have a dual nature in that they show both hydrophilic (water-loving) and hydrophobic (water-fearing) properties • The amphipathic nature of phospholipids causes them to spontaneously form bilayers in water based solutions o The inner and outer surfaces of the bilayers are hydrophilic and can interact with the aqueous environment, while the core of the bilayer is hydrophobic and able to exclude water and other polar molecules o Because of these properties, phospholipids bilayers are able to serve multiple functions including: ▪ act as barriers to protect the cell from the outside environment ▪ house proteins and carbohydrates necessary for cell to cell and extracellular communication ▪ organize and provide surface areas for metabolic reactions • While the phospholipids bilayer is a highly organized system with multiple functions, it is also highly dynamic and can be functionally described using the fluid mosaic model (FMM) o FMM characterizes the phospholipids bilayer of the cell membrane as highly dynamic and fluid meaning that the position (location) of any given phospholipids in the membrane is not fixed but fluid; thus, individual phospholipids can change positions are needed based on the current conditions. o Similarly proteins and carbohydrates are generally mobile in the membrane as well. • This experiment was aimed at investigating the conditions that affect cell membrane integrity. o Because cell membranes are part of a living system they are sensitive to environmental conditions o Like most biological systems, cell membranes show a relatively narrow
Introduction: • Cell membranes are vital to proper cellular function • Cell membranes consist of a lipid bilayer made up of phospholipids • Phospholipids are amphipathic molecules meaning they have a dual nature in that they show both hydrophilic (water-loving) and hydrophobic (water-fearing) properties • The amphipathic nature of phospholipids causes them to spontaneously form bilayers in water based solutions o The inner and outer surfaces of the bilayers are hydrophilic and can interact with the aqueous environment, while the core of the bilayer is hydrophobic and able to exclude water and other polar molecules o Because of these properties, phospholipids bilayers are able to serve multiple functions including: ▪ act as barriers to protect the cell from the outside environment ▪ house proteins and carbohydrates necessary for cell to cell and extracellular communication ▪ organize and provide surface areas for metabolic reactions • While the phospholipids bilayer is a highly organized system with multiple functions, it is also highly dynamic and can be functionally described using the fluid mosaic model (FMM) o FMM characterizes the phospholipids bilayer of the cell membrane as highly dynamic and fluid meaning that the position (location) of any given phospholipids in the membrane is not fixed but fluid; thus, individual phospholipids can change positions are needed based on the current conditions. o Similarly proteins and carbohydrates are generally mobile in the membrane as well. • This experiment was aimed at investigating the conditions that affect cell membrane integrity. o Because cell membranes are part of a living system they are sensitive to environmental conditions o Like most biological systems, cell membranes show a relatively narrow