Active
transport uses energy to move a solute "uphill" against its gradient,
whereas in facilitated diffusion, a solute moves down its concentration
gradient and no energy input is required.
Passive transport requires no energy from the cell. Examples include the diffusion of oxygen and carbon dioxide, osmosis of water, and facilitated diffusion.
Types of passive transport.
Active transport requires the cell to spend energy, usually in the form of ATP. Examples include transport of large molecules (non-lipid soluble) and the sodium-potassium pump.
