Cell Membrane Structure Flashcards
What two types of structures can phospholipids form?
-A bilayer
-A micelle
What is the role of the cell membrane?
To keep contents inside the cell.
-Allows select molecules in and out of the cell.
-Isolates organelles from cytoplasm so reactions can occur
-Allows cell to change shape.
-Sit of chemical reactions.
Who was the fluid mosaic model proposed by and when?
Singer and Nicholson in 1972.
What does the fluid mosaic model suggest?
-All proteins are found within the cell.
-The phospholipids can move in the bilayer.
-Proteins are arranged unevenly.
Which molecules can pass through the bilayer?
-Water is polar but can move through slowly.
-Lipid soluble molecules can pass through.
-Small molecules.
What molecules cannot pass though the bilayer?
-Charged molecules/ions.
-Larger uncharged molecules are transported by proteins (glucose).
-Water soluble molecules.
What makes the model fluid?
-The phospholipids moving in the bilayer like a liquid.
What creates the mosaic part of the model?
Proteins inside the bilayer and scattered unevenly creating a mosaic pattern.
What are the 9 components of a cell membrane?
-Glycolipids
-Intrinsic proteins
-carbohydrate
-Glycoprotein
-Phospholipid bilayer
-Extrinsic proteins
-Cholesterol
-On a phospholipid- Hydrophobic tail and a hydrophilic head.
What is the role of glycolipids?
-Acts as a recognition site.
-Maintains stability of the membrane.
What is a glycolipid?
A carbohydrate covalently bonded with a lipid.
What is the difference between intrinsic and extrinsic proteins?
-Intrinsic is one one side of the membrane.
-Extrinsic are throughout the cell membrane.
What is the role of proteins found inside the cell membrane?
-Can transport substances across the membrane as some are channel and carrier proteins.
What is the role of a glycoprotein in the membrane?
-Acts as a recognition site.
-Helps cells attach to tissues so they can recognise self-cells.
What is the role of cholesterol in the membrane?
-Adds strength to the membrane.
-Stops it from become too fluid at high tempretures.
