Cellular Membrane Quiz Flashcards
What is the function of the Plasma Membrane?
To control what enters and leaves the cell
Selective Permeability
Somethings are allowed to pass while others are rejected
What are the molecules of the plasma membrane?
Phospholipids Proteins Carbs Cholesterol CHO
Amphipathic
Hydrophobic and Hydrophilic region
Which part of a phospholipid is polar and hydrophilic?
The head
Which part of a phospholipid is nonpolar/hydrophobic
The tail
Examples of amphipathic molecules
Phospholipids and membrane proteins
Fluid Mosaic Model
Phospholipids and proteins drift laterally within the membrane
How fast do phospholipids move?
100,000,000 times/ second
Compared to phospholipids, how fast to membrane proteins move?
Slower
Describe the relationship between fluidity and temperature.
As temperature increases, fluidity increases
Tell about fluidity and membrane composition
Unsaturated fatty acid tails are kinked and prevented from tight packing
How does cholesterol affect the plasma membrane at warmer temps?
At higher temps, cholesterol restricts phospholipid movement
How does cholesterol affect the plasma membrane at cooler temps?
Acts as a wedge between phospholipids preventing tight packing.
What type of cell is cholesterol found in?
Animal cells ONLY