Fruit Fly Ovary (IMAGE) Stowers Institute for Medical Research Caption A bam mutant fruit fly ovary, known as the germanium, contains only adult stem cell-like cells (red) and spherical spectrosome (green). The accumulation of only adult stem cell-like cells indicates a mutation in the master differentiation factor bam completely blocks germline stem cell lineage differentiation. Credit Courtesy: Ting Xie, Ph.D., Stowers Institute for Medical Research Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.