What type of radiation is most penetrating and can pass through human tissue?

Gamma radiation is indeed the most penetrating type of radiation and is capable of passing through human tissue. This high penetrability is due to the nature of gamma rays, which are high-energy electromagnetic waves. Unlike alpha particles, which consist of two protons and two neutrons and can be stopped by a sheet of paper or even a few centimeters of air, and beta particles, which are high-energy electrons that can penetrate a few millimeters into human tissue but are still easily shielded by materials like plastic or glass, gamma rays travel at the speed of light and require denser materials, such as lead or several centimeters of concrete, to effectively attenuate their energy.

X-rays also possess high energy and can penetrate human tissue, but they are generally less penetrating than gamma rays. Gamma radiation's ability to deeply penetrate materials, including biological tissues, makes it significant in both medical applications and in understanding radiation safety and protection principles.