The structure of cell membranes Flashcards
what do all cell membranes contain ?
They’re composed of lipids (mainly phospholipids), proteins and carbohydrates (attached to proteins or lipids).
when did the fluid mosaic model emerge ?
1972
what does the fluid mosaic model do ?
describe the arrangement of molecules in the membrane.
describe the fluid mosaic model ?
phospholipids join a continuous double layer (a bilayer ).proteins are scattered through the bilayer( some are channel ,receptorss and carrier )
why is the fluid mosaic model described as fluid ?
the phospholipids are constantly moving .
why is the fluid mosaic model described as mosaic ?
there a proteins scattered about like tiles in a mosaic
what proteins are in the fluid moasaic model and what do they allow ?
channel proteins and carrier proteins, which allow large molecules and ions to pass through the membrane.
Receptor proteins on the cell-surface membrane allow the cell to detect chemicals released from other cells.
why are the chemicals detected by the receptor proteins important ?
The chemicals signal to the cell to respond in some way
explain insulin and receptor proteins ?
the hormone insulin binds to receptor proteins on liver cells, which tells the cells to absorb glucose.
can proteins move in the phospholipid bylayer?
Some proteins are able to move sideways through the bilayer, while others are fixed in position.
what are glycoproteins ?
proteins have a carbohydrate attached
what are glycolipids ?
lipids that have a carbohydrate attached
what two types of lipids are present in the bilayer ?
cholesterol and phospholipids
