L4-6 quiz

• cholesterol functions in the plasma membrane to:

  maintain fluidity
• how does cholesterol increase the fluidity and stability of the membrane:

  by interacting with the phospholipids
• lipid synthesis occurs in which eukaryotic organelle?


  smooth endoplasmic reticulum
• lysosomes function:

  • catalyse the rapid breakdown of macromolecules
  • break down old organelles
  • eliminate substances taken into the cell by phagocytosis
  • participate in apoptosis (cell selective death)
• marker molecules on the outer plasma membrane are:

  carbohydrate chains e.g. blood group antigens on red blood cells
• some ribosomes are embedded into:

  rough endoplasmic reticulum
• rough endoplasmic reticulum is where:

  extracellular and membrane proteins are synthesised
• fluid nature of the membrane is attributed to a lateral movement of the entire lipid bilayer
• part of a membrane protein that extends through the phospholipid bilayer is primarily composed of amino acids that are:

  non-polar (or hydrophobic region)
• cell eating is often called

  phagocytosis, used by special white blood cells called phagocytes
• what is found in the cytoskeleton?

  • actin filaments
  • intermediate filaments
  • spindle fibres
  • microfilaments
• membrane protein classes?


  transport channels, receptors, enzymes and antigenic markers