Co-workers: Adelfa Masculino Date Performed: June 29, 2012
Farrah Belle Barredo
The Cell Membrane
The boundary between any cell and its environment is the plasma membrane, composed of a matrix of phospholipid molecules along with a number of different kinds of proteins. Membranes have different properties and a variety of functions, in large part determined by the specific proteins within the membrane. This experiment is designed to determine the stress that various factors, such as osmotic balance, detergents and pH, have on biological membranes. There are three parts in this experiment. The first part is the synthesis of an artificial membrane. In this experiment, the vegetable oil was added with albumin solution and the albumin bubble breaks, but didn’t rupture but when water was added in vegetable oil, the water breaks easily than the albumin and it didn’t mix with the oil. When albumin was added into the vegetable oil, a bubble forms because air is introduced into the system. The bubble formed remained stable due to protein adsorption at the bubble surface. Water bubble on the other hand breaks easily because it is less viscous than albumin. The second part is the determination of osmotic effect in frog’s blood, mammalian blood and plant. The frog and mammalian bloods are subjected to different NaCl concentrations: 0.1%, 0.7% and 0.16 M, while the plant (Rheo discolor) is subjected to 0.3 M glucose. When the frog and mammalian bloods are subjected to 0.1 % NaCl, an influx of water occurs: the cells swell, the integrity of their membranes is disrupted, allowing the escape of their hemoglobin in the process of hemolysis because the solution is hypotonic. When 0.7% NaCl was added to the bloods, there is no net influx or efflux of water because the solution is isotonic. When 0.16 M NaCl was added to the bloods, the cells lose their normal biconcave shape,...