Alpha radiation consists of particles made up of two protons and two neutrons, which are identical to the nucleus of a helium atom. These particles are emitted during the decay of certain heavy elements, such as uranium and radium. Alpha radiation has low penetration power and can be stopped by a sheet of paper or even human skin. Despite its limited ability to penetrate materials, alpha radiation can be harmful if ingested or inhaled. Inside the body, alpha particles can cause significant damage to cells and tissues, leading to potential health risks, including cancer.