Movement in and out of cells
Helen Moth
The cell membranes main function is to serve as a boundary between the cell and it’s environment. It is just like other organelles in the cell in that it serves the cell by having it’s own specialised jobs.
In terms of beetroot the purple pigment is contained within the cell membrane, if this membrane is disrupted the pigment will be released.
Temperature may be the cause of the disruption. High temperatures could distort the “active site” of the carrier, channel of gated proteins, therefore affecting the shape of the fluid mosaic model membrane which may release molecules that normally would not be allowed to be released (in our case the purple pigment), or allow other molecules in. Temperature basically disrupts facilitated diffusion.
The picture above shows a close up view of a cell membrane, cell membranes are made up of fat molecules, or to be more specific phospholipid molecules with various large intrinsic and extrinsic, globular proteins suspended in them.
Molecules move across cell membranes by two major processes, diffusion, or active transport. Diffusion is the movement from a high concentration of molecules to a low concentration. Molecules can diffuse across membranes through the phospholipid bi-layer or through special carrier proteins. It is important that neither of these types of diffusion need energy to make them work. However active transport does require energy. If the cell requires molecules to enter the cell against the gradient, it needs energy for example channel proteins need energy to move certain molecules into the cell the energy comes from ATP, which is made in the mitochondria.
