الفهرس | Only 14 pages are availabe for public view |
Abstract The thesis aims to study the effect of environmental factors to which living organisms are exposed and their effect on DNA, such as the effect of chemicals, including cement and cigarettes, and their cumulative exposure in an amount of (1, 2, 3, 4) μL from each of them, and also to study the effect of some rays such as the laser Green beam 532 nm with a power of 100mW and gamma rays 221 kev for the element cobalt 57. Also cumulatively (5, 10, 15, 20, 25, 30) minutes for each of them individually and studying the electrical impedance when applying a fixed voltage at a certain frequency. Studies also take different cancer samples to study the extent to which cancer DNA is affected by these factors. Environmental chemicals present a variety of difficulties for living organisms, primarily through toxicity or mutagenicity. Mutations occur when adducts are chemically added to bases or when changes occur in the base sequence in DNA. These modifications hinder the correct transcription of DNA into RNA and/or DNA replication. Moreover, spontaneous mutation of DNA bases can also occur by dyeing, deletion, or addition of bases, deamination, etc. It is dealt with through one of several DNA repair processes found in human cells every day. In each cycle, DNA replication itself causes some fundamental modifications. Before undergoing programmed cell death (programmed cell death), cells divide between 40 and 70 times to protect themselves from accumulating mutations. |