Temperature And Membranes

Question 1

Why does temp affect cell membranes ?

Answer 1

It affects how much the phospholipids in the bilayer can move - affects membrane permeability and structure.

Question 2

Temp below 0 degrees

Answer 2

Phospholipids don’t have much energy, don’t move much.
Packed closely together/ rigid.
Channel/ carrier proteins denature
Increase in permeability of membrane
Ice crystals may form and pierce the membrane making it highly permeable when it thaws.

Question 3

Temp between 0 and 45 degrees

Answer 3

Phospholipids can move around and aren’t tightly packed together.

Partially permeable.

As temp increases the phospholipids move more as they have more kinetic energy increasing the permeability of membrane.

Question 4

Temps above 45 degrees

Answer 4

Phospholipid bilayer starts to melt.

Membrane more permeable.

Water inside cells expand putting pressure on membrane.

Channel proteins and carrier proteins denture so no control of what enters and exits cell - increasing permeability of cell.