The spelling of "excision repairs" corresponds to the phonetic pronunciation /ɪkˈsɪʒən ɹɪˈpɛəz/. In this word, the "excision" portion is spelled with an "x" to represent the /ks/ sound at the beginning, followed by the phonetic spelling of "sision" to represent the /sɪʒən/ sound. The second word, "repairs," is spelled phonetically as /ɹɪˈpɛəz/, with the "ea" combination representing the /ɛə/ sound and the "s" at the end representing the /z/ sound. Understanding phonetic transcription can aid in correctly pronouncing and spelling words.
Excision repairs refer to a set of highly intricate molecular mechanisms employed by cells to rectify damaged or abnormal DNA molecules. One of the fundamental processes involved in maintaining the integrity of the genetic material, these repairs involve the removal and subsequent replacement of incorrect, mismatched, or damaged nucleotides. Specifically, excision repair mechanisms act upon chemical alterations, distortions, or distortions incurred by DNA molecules due to various forms of cellular stress, including exposure to genotoxic agents like certain chemicals, ultraviolet (UV) radiation, or ionizing radiation.
The excision repair process typically operates in distinct stages. First, specialized enzymes, known as excision nucleases or endonucleases, pinpoint the damage site by recognizing specific structural abnormalities or chemical alterations within the DNA strand. These nucleases initiate the process by creating incisions in the DNA near the damaged region. Subsequently, another group of enzymes, called DNA polymerases, proceeds to synthesize a complementary DNA strand, filling in the excised region. Finally, the newly synthesized DNA strand is sealed by another enzyme, DNA ligase, which permanently rejoins the DNA backbone, ensuring the integrity of the repaired molecule.
Overall, these sophisticated excision repair mechanisms play a crucial role in maintaining the stability and fidelity of the genetic material, thereby preventing the accumulation of mutations and the development of various genetic disorders or diseases.
The term "excision repair" originated in the field of molecular biology and genetics. It is a compound word formed by combining two separate words: "excision" and "repair".
The word "excision" derives from the Latin word "excisio", which means "a cutting out or removal". It can also be traced back to the Latin verb "excīdĕre", meaning "to cut out" or "to cut off". In the context of molecular biology, "excision" refers to the removal or cutting out of damaged DNA segments.
The word "repair" has its roots in the Old French word "reparer", which means "to restore" or "to mend". It is derived from the Latin word "reparare", which carries the same sense of "to restore".