4 Written Questions

1. the movement of water from a region of higher concentration to a region of lower concentration, passing through a selectively permeable membrane
2. gatekeeper, structure and support, recognizes foreign materials, and communicates with other cells
3. the movement of a substance from a region of higher concentration to a region of lower concentration
4. most often a molecule that serves to carry information between cells

4 Multiple Choice Questions

1. a substance, generated when a signal molecule binds with a receptor protein, that serves as a signal inside the cell
   1. osmosis
   2. receptor protein
   3. second messenger
   4. channel protein
2. a substance, located in the cell membrane and made of amino acids, which other substances can pass through to cross the cell membrane
   1. channel protein
   2. receptor protein
   3. carrier protein
   4. phospholipid
3. this specialized lipid is made up of a phosphate head and two "fatty acid" tails
   1. osmosis
   2. equilibrium
   3. diffusion
   4. phospholipid
4. the state in which the distribution of a substance is even throughout a region
   1. signal
   2. diffusion
   3. osmosis
   4. equilibrium

4 True/False Questions

1. carrier protein → a substance, located in the cell membrane and made of amino acids, which other substances can pass through to cross the cell membrane

   True        False

2. cell membrane structure → a double layer of phospholipids

   True        False

3. receptor protein → a substance, located in the cell membrane and made of amino acids, that binds with specific molecules, causing a change in the cell

   True        False

4. cell-surface marker → a double layer of phospholipids

   True        False