Cell Membrane Flashcards
structure and function
1
Q
What is a cell membrane made of?
A
Phospholipid bi-layers
Cholesterol
Proteins
2
Q
Role of a cell membrane?
A
- makes a physical barrier
- regulate the passage of materials
- sensitive to external environment
- provides support for the cell
3
Q
Structure of the phospholipid bilayer
A
- phospholipids are made from a phophate head (hydrophilic) and a lipid tail (hydrophobic)
- in the bi-layer, the tails bump up against each other and the phosphate heads face outward
4
Q
Why is the model for the cell membrane called the fluid mosaic model
A
- fluid: molecules that it’s made of are constantly moving/changing positions
- mosaic: it’s made of many different kinds of molecules
5
Q
Cell requirements?
A
- needs to be in a stable environment
- needs a continual supply/removal of materials
6
Q
What are the types of membrane proteins? (there’s five)
A
- receptor
- channel
- carrier
- cell-identify markers
- glycoproteins
7
Q
What are channel proteins
A
- open channels that allow for simple diffusion
8
Q
What are carrier proteins
A
- proteins that allow for facilitated diffusion and active transport
- only opened when stimulated by the correct molecules
