Cholesterol

• where may cholesterol also be present?

  in other membranes where it restricts the movement of other molecules making up the membrane
• what is cholesterol a type of?

  lipid
• what does cholesterol give the membrane?


  stability
• where is cholesterol present?

  in all cell membranes

  • EXCEPT BACTERIAL CELL MEMBRANES
• Where do cholesterol molecules fit?

  between the phospholipids
• What do cholesterol molecules bind to?

  The hydrophobic tails of the phospholipids, causing them to pack more closely together

  • This restricts the movement of the phospholipids, making the membrane less fluid and more rigid
• What does cholesterol help ANIMAL CELLS to do?

  Maintains the shape of animal cells (which DO NOT have CELL WALLS)

  • Particularly important for cells that are not supported by other cells
• why is cholesterol particularly important for cells such as red blood cells?

  float free in the blood

  are not supported by other cells