Permability of cell Membrane

Question 1

The Membrane as a barrier

Answer 1

Cell surface is selectivrly permable to water and some solutes
Lipid solublr ( non-polar ) can move through the membrane more easier than water soluble ( polar ) substances

Question 2

Non-polar molecules

Answer 2

Small uncharged molecules like oxygen and carbon dioxide freely pass through because of diffusion
Lipid soluble molecules, like glycerol can also pass through the membrane, through the phospholipid bilayers

Question 3

Polar molecules

Answer 3

Hydrophobic core of the membranes impeads the transport of ions and polar molecules
Charged particles and relitively charged molecules like glucose can’t diffuse because they are insoluble in lipids
Intrinsic proteins allows thses particles to cross the membrane
Channel and carrier proteins allow facilitated diffusion
Pumps carry out active transport