This is Episode 2b, DNA Repair: Single-Strand Breaks& NHEJ.Last time, we delved into Base Excision Repair andNucleotide Excision Repair, the cell's tools for fixing damaged bases and bulkylesions. But ionizing radiation does more than just damage bases – itfrequently breaks the sugar-phosphate backbone of DNA. Today, we'll explore howcells handle single-strand breaks and introduce the first major pathway forrepairing the most critical radiation-induced lesion: the double-strand break,specifically focusing on the fast but potentially risky pathway called Non-HomologousEnd Joining, or NHEJ.