To produce an electric current, three things are needed: a supply of electric charges (electrons) which are free to flow, some form of push to move the charges through the circuit and a pathway to carry the charges. The pathway to carry the charges is usually a copper wire.
A cell wall builds protein without a membrane
Radiation is the transfer of energy in the form of rays or waves. There are many forms of radiation, such as electromagnetic radiation. This is the most familiar form, and includes radio waves, microwaves, visible light rays, and x-rays.
