Membrane Transport
facilitated diffusion
A molecule moves down its concentration gradient using a transport protein in the plasma membrane. This is an example of
endocytosis
The plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell. This describes the process of
active transport
The sodium-potassium pump uses energy from ATP to move sodium ions out of the cell, and potassium ions into the cell. This is an example of
through facilitated diffusion or diffusion
Water crosses the plasma membrane
active transport
molecules move across the plasma membrane against their concentration gradient.