plasma membrane

Question 1

how does temperature affect membrane

Answer 1

• the higher the temperature of a membrane the more kinetic energy it has and it will move more
• this makes the membrane more fluid and it begins to lose its structure
• if the temperature continues to rise the membrane will break down completely
• the loss of structure makes increases the permeability of the membrane making it easier for particles to cross it
• carrier and channel proteins in the membrane will be denatured at higher temperatures, this will affect permeability

Question 2

how do solvents affect membranes

Answer 2

• water keeps the structure of the bilayer by interacting with the polar phosphate heads
• less polar or none polar organic solvents will dissolve membranes disrupting the cell
• less concentrated alcohol will damage cell membranes whereas pure alcohol will destroy cells
• when the membrane is disrupted it becomes more fluid and more permeable