Blood flows from the vena cava into the right atrium of a man’s heart. A valve opens and allows the blood to flow into the right ventricle, then closes, allowing the blood to flow one way, back into the man’s body. The valve is attached to the wall of the man’s heart with plastic.
Power is transmitted through a wire to light up a living room, charge a smartphone, power a washing machine or heat up an electric stove. The power flows through wire coatings made of plastic which help insulate, protect and prevent the wires from overheating and causing potential damage.