VI.  Active Transport

    A.  Active Transport - transport of materials against a
         concentration gradient which REQUIRES ENERGY

    B.  Active Transport for small ions usually happens
          through carrier proteins and uses ATP for energy
 
 

VII.  Transport of Large Particles

    A.  Transport of large particles happens by active transport
          because the process REQUIRES ENERGY

    B.  Endocytosis - a process in which a cell surrounds and
          takes in material from its environment

        1.  Phagocytosis - transport of large particles of solid
             food or whole cells into the cell

        2.  Pinocytosis - transport of liquid droplets or smaller
             particles into the cell

    C.  Exocytosis - a process in which a cell transports large
          particles out of the cell