Answer:
passive transport
Explanation:
Diffusion is one of the ways molecules/substances move or is transported. It is the process whereby substances move from a region of higher concentration to a region of lower concentration until there is an even distribution. Movement via diffusion occurs down a concentration gradient i.e high to low.
Since diffusion occurs down a concentration gradient, which is difference in concentration of a substance, it requires no energy in form of ATP to occur. This kind of transport which requires no energy input is called PASSIVE TRANSPORT, in contrast to active transport which requires.
