Final answer
Ionizing radiation and oxidative damage can beget DNA double-beachfront breaks. After damaged DNA has been repaired, hacks in the phosphate backbone aren't maintained. Depurination of DNA isn't caused by ultraviolet irradiation. Nonhomologous end joining isn't a medium that ensures a high degree of dedication to the original DNA sequence.
Explanation
True. Ionizing radiation and oxidative damage can indeed beget DNA double-beachfront breaks. Ionizing radiation, similar as X-rays and gamma shafts, can lead to the conformation of single-stranded and double-stranded breaks in the sugar-phosphate backbone of DNA. Oxidative damage, which occurs due to the presence of reactive oxygen species, can also beget double-beachfront breaks in DNA.
False. After damaged DNA has been repaired, hacks in the phosphate backbone aren't maintained as a way to identify the repair beachfront. Once the DNA is repaired, the integrity of the phosphate backbone is restored without any hacks.
False. Depurination of DNA isn't caused by ultraviolet( UV) irradiation. Depurination refers to the hydrolytic junking of guanine or adenine from the deoxyribose in a DNA beachfront. It can work spontaneously or due to other causes, but not specifically due to UV irradiation.
False. Nonhomologous end joining( NHEJ) is a medium that repairs DNA double-beachfront breaks, but it doesn't ensure a high degree of dedication to the original DNA sequence. NHEJ is an error-prone form pathway that rejoins the broken ends of DNA without taking a template. This can affect the loss or addition of nucleotides, leading to inheritable changes.