2. immune globulin. gamma rays (Î³-rays) electromagnetic emissions from radioactive substances; they are similar to and have the same general properties as x-rays but are produced through the disintegration of certain radioactive elements.. immune globulin. gamma rays (Î³-rays) electromagnetic emissions from radioactive substances; they are similar to and have the same general properties as x-rays but are produced through the disintegration of certain radioactive elements.
3. The chromosomes in the cell nucleus would contain the most radioactivity because thymine is part of the DNA molecule and chromo-somes are composed of DNA. Inclusion/Special Needs Show students a picture of a bacterial cell and an animal cell. Talk about the location of DNA in each cell and where DNA replication occurs.
Discovery of Radioactivity. The discovery of radioactivity took place over several years beginning with the discovery of x-rays in 1895 by Wilhelm Conrad Roentgen and continuing with such people as Henri Becquerel and the Curie family. The application of x-rays and radioactive materials is far reaching in medicine and industry.