Plasma Membrane Flashcards
Plasma Membrane
Function: controls the passage of materials into and out of a cell
- Bilayer of phospholipids
It is semipermeable
Semi-permeable
Only some materials may exit or enter
What parts make up a phospholipid
Polar Head:
1. Phosphate group
2. Glycerol
Nonpolar Tail:
3. Two chains of fatty acids
Arrangement of Phospholipids
Outside: Polar Head
Inside: Nonpolar Tails
Fluid Mosaic Model of Plasma Membrane Parts
- Cholesterol
- Carbohydrates
- Protein Channel
- Cytoskeleton
Cholesterol Role
Helps prevent phospholipids from separating too far from one another, keeps the plasma membrane compact and bound together. Also gives the membrane its flexibility.
Phospholipid Role
Helps provide a structure for the plasma membrane
Carbohydrates
Used for identification or recognition purposes, referred to as a receptor as this is a way our immune system knows when to attack foreign cells.
Protein channel
Made up of proteins, allows certain objects that cannot pass through the phospholipids bilayer such as larger molecules or charged molecules.
Cytoskeleton
Protein threads that not only provides internal structure but creates a pathway for molecule transport
Why is the plasma membrane mosaic
The plasma membrane is said to be mosaic due to its wide variety of components
Why is the plasma membrane fluid
The plasma membrane gets its fluidity from how the components can drift around and are in motion
Polar molecule
Molecule where one area has a positive charge while another area has a negative charge
