Permeability of cell membrane

Question 1

permeability of cell membrane - as a barrier

Answer 1

• cell membrane surface is selectively permeable to water and some solutes
• non-polar substances can move through easier than polar substances

Question 2

permeability of cell membrane - lipid-soluble substance

Answer 2

• can dissolve in phospholipids and diffuse across
• phospholipid layer hydrophobic, lipid-soluble passes thorugh easier than water-soluble substances

Question 3

permeability of cell membrane - water-soluble substances

Answer 3

• can’t diffuse through the phospholipids
• must pass through intrinsic protein - which form water-filled channels across