membranes and membrane transport

    Cards (24)

    • how are phsopholipid bilayers formed
      a hydrophilic phosphate head bonds with 2 hydrophobic hydrocarbon tails
    • what happens when phospholipids are placed in water
      the hydrophilic phosphate heads orient towards the water and the hydrocarbon tails orient away from the water
    • what properties of the phospholipid bilayer allow it to form a barrier
      large molecules cannot pass through, polar molecules and ions cannot pass through
    • what are two categories of membrane proteins
      integral and peripheral
    • what are integral membrane proteins
      amphipathic, embedded in the phospholipid bilayer
    • what are peripheral membrane proteins
      hydrophilic, attached to either surface of integral proteins, can be inside or outside the cell
    • what are 2 types of transport proteins
      channel and carrier
    • what are channel proteins
      they form holes or pores where molecules can travel through
    • what are carrier proteins
      they change shape to transport a substance across the membrane
    • what is simple diffusion
      a type of membrane transport that involves particles passing directly between the phospholipids in the plasma membrane
    • what are examples of molecules that move by simple diffusion
      oxygen and carbon dioxide
    • what are some factors which effect the rate at which a substance diffuses across a membrane
      temperature, surface area, properties of the molecule
    • what is facilitated diffusion
      when substances can only cross the phospholipid bilayer with the help of transport proteins
    • what are the types of proteins that enable facilitated diffusion
      channel and carrier
    • what are channel proteins
      A) channel protein
      B) phospholipid bilayer
    • what are carrier proteins
      A) phospholipid bilayer
      B) carrier protein
    • what is selective permeability
      the ability of the membrane to differentiate between different types of molecules
    • how does ATP release energy
      it is hydrolysed
    • what are glycoproteins
      cell membrane proteins that have a carbohydrate chain attached on the extracellular side (outside cells)
    • what are glycolipids
      lipids with carbohydrate chains attached on the outside cells
    • what do glycoproteins and glycolipids do
      the carbohydrate chain enables them to act as receptor molecules
    • who outlined the fluid mosaic model of membranes
      singer and nicolson, 1972
    • what does the fluid mosaic model describe cell membranes as
      fluid - proteins and phospholipids can move around within the layers
      mosaics - scattered pattern produces by the proteins within the layer
    • what is the fluid mosaic model
      A) glycolipid
      B) glycoprotein
      C) cholesterol
      D) peripheral protein
      E) integral protein
      F) channel protein
      G) hydrophilic phosphate head
      H) hydrophobic fatty acid tail