Phospholipids are the most
Abundant lipid in the plasma membrane
Phospholipids are amphipathic molecules, containing?
hydrophobic and hydrophilic regions.
What does the fluid mosaic model state?
that a membrane is a fluid structure with a "mosaic of various proteins embedded in it.
Cellular Membranes are made of what?
Proteins and lipids
Phospholipids in the plasma membrane can move
within the bilayer
Most of the lipids and some proteins
drift laterally
Rarely does a molecule
flip-flop transversely across the membrane.
As temperatures cool,membranes
switch from a fluid state to a solid state
What depends on the types of lipids?
the temp at which a membrane solidifies
Membranes rich in unsaturated fatty acids are?
are more fluid than those rich in saturated fatty acids
Membranes must be what to function properly?
Fluid (usually about as fluid as salad oil)
The steroid cholesterol has different effects on what?
Membrane fluidity at different temperatures
At warm temperatures (such as 37c)
cholesterol restrains movement of phospholipids
At cool temperature it maintains fluidity by
preventing tight packing