A study on the effect of varying temperatures on the permeability of the plasma membrane of Brassica oleracea
Introduction
Occasionally, my mother would make homemade juices for my grandma. The juice contained various types of vegetables and fruits such as kale, spinach, kiwi, apple, banana, and red cabbage. To make the juice, the vegetables and fruits are blended in distilled water, which produces a purple color. My mother wants to maximize the purple pigment within the juice to improve the overall appearance of it. She discovered that the temperature of the distilled water used had affected the strength of the pigment. Taking this into consideration, I will be helping my mother find out the optimum temperature of distilled water required
The phosphate sits on the surface of the cell plasma as they are hydrophilic; while the fatty acid chains are situated away from the cell plasma as they are hydrophobic. The phospholipid membrane’s two main functions are to control the transport of materials, and to maintain pigments and carrier proteins in fixed positions within chloroplasts and the mitochondria.
The first model of the plasma membrane was theorized by J.F. Danielli and H. Davson in late 1930’s, who stated that there was a protein layer between the bimolecular lipid layers. However, it was in 1972 when J.J. Singer and G.L. Nicholson put forward their ‘fluid-mosaic model’, which consisted of flexible fatty acid chains and proteins that were not of a continuous membrane but scattered throughout the bilayer in globules.
The plasma membrane is usually between 6-10nm thick, and is only visible through an electron microscope. The structure of the plasma membrane consists of two layers of phospholipids, embedded with many protein molecules. It is described as a ‘fluid-mosaic’ as the membrane proteins are unevenly distributed throughout the bilayer, so the pattern resembles somewhat of a mosaic. Also, the bilayer is fluid, meaning that the protein molecules are not fixed but constantly