Final answer:
Ionizing radiation, such as X-rays and gamma rays, can remove electrons from molecules, while non-ionizing radiation, like light and microwaves, cannot. UV light, a form of non-ionizing radiation, controls microbial growth by forming thymine dimers in DNA, leading to mutations and cell death. UV light is effective for disinfection but requires direct exposure and does not penetrate surfaces.
Step-by-step explanation:
The difference between ionizing and non-ionizing radiation lies in their energy levels and biological effects. Ionizing radiation includes high-energy emissions such as alpha (α) and beta (β) particles, gamma (γ) rays, X-rays, and high-energy ultraviolet radiation. This type of radiation is powerful enough to knock electrons out of molecules, causing ions to form. Examples of ionizing radiation are X-rays and gamma rays, commonly used in medical imaging and cancer treatment.
Non-ionizing radiation includes lower-energy forms like light, microwaves, and ultraviolet (UV) light. While it doesn't have enough energy to ionize atoms or molecules, it can lead to molecular excitations. Examples of non-ionizing radiation are microwaves and UV light. The UV light specifically limits microbial growth by causing the formation of thymine dimers within DNA, leading to mutations and eventually cell death, making it useful for disinfection in water purification systems, surgical suites, and biological safety cabinets.
The effectiveness of UV light as a disinfectant is because it interrupts the DNA replication process in microbes. However, its limitation is that it does not penetrate surfaces well and must be used where direct exposure to the light source is possible.