Cell Membrane:

Cell Membrane:

• Cell membrane is made up of a phospholipid bilayer.
• The phosphate head of the phospholipid is a polar molecule and attracts water – it is hydrophilic.
• The fatty acid tails are non-polar and hydrophobic.
• In the cell membrane, the hydrophobic tails face inwards to avoid water, while the hydrophilic heads point outwards.
• In the phospholipid bilayer are other molecules:
• Proteins: some are fixed, while others move around. May be enzymes, carriers, or channels.
• Cholesterol: reduces the fluidity of membrane by preventing movement of phospholipids.
• Glycoproteins: (polysaccharide + protein) cell recognition and receptors
• Glycolipids: (polysaccharide + lipid) cell recognition and receptors