Cell Membrane and Transport Study Guide

Name:______per______

  1. Why do we call a cell membrane:
  2. Fluid – the phospholipids are free to move around. They are not fixed in place.
  1. Mosaic- membrane is made of many small parts put together to make the whole.
  1. Semipermeable (or selectively permeable)- only allows some things to pass and not others
  1. Phospholipid bilayer- Made of two layers of phospholipids
  1. Explain how exocytosis andendocytosis occur…draw a simple picture to help.

  1. Compare/Contrast:
  2. Osmosis and diffusion- Osmosis is the diffusion of water molecules. They are both passive transports that move particles from high to low concentration.
  1. Simple diffusion/facilitated diffusion- They are both passive transports that move particles from high to low concentration, but facilitated diffusion must use a channel protein whereas simple diffusion just occurs across the membrane directly.
  1. Exocytosis and endocytosis-Both are ways to move large amounts of material in and out by creating a vesicle out of phospholipids. Exocytosis is how materials are moved OUT, and endocytosis is how materials are brought INTO the cell.
  1. Active vs. passive transport- Active transport requires energy. It includes using a carrier protein to move particles from low to high concentration across a membrane. Passive transport does NOT require energy and flows from high to low concentration. It includes Simple Diffusion and Facilitated Diffusion.
  2. Active transport and facilitated diffusion They both involve proteins, but facilitated diffusion just flows from high to low concentration through a channel protein without needing any energy. Active transport uses a carrier protein and energy to carry particles from low to high concentration.
  1. Label the following on the diagram below:

  1. Hydrophobic region
  2. Hydrophilic region
  3. Carrier protein
  4. Channel protein
  5. Glycoprotein

Use the pictures below to answer the questions. Remember “solution” refers to the liquid OUTSIDE the cell.

ABC

  1. ____C___ Which situation below shows an ISOTONIC solution?
  2. ____A___ Which situation below shows a HYPERTONIC solution?
  3. ____B__ Which situation below shows a HYPOTONIC solution?
  4. ____C___ Which will have an equal amount of water come into & out of the cell?
  5. ____B___ Which one will have water enter the cell?
  6. ____A__ Which will have water leave the cell?
  7. ____B__ Which would cause the cells to swell or burst?
  8. ____A__Which would cause a plant to wilt?