Final answer:
The fluorescence in genetically engineered organisms signifies the activation of the introduced gene, which is crucial for researchers to confirm successful genetic modification for creating transgenic plants and animals with beneficial characteristics.
Step-by-step explanation:
The value of creating fluorescent genetically engineered organisms, such as tobacco plants and fluorescent fish, is that the fluorescence indicates whether the inserted gene is active or not. Fluorescent markers are a common genetic engineering tool that allow scientists to easily identify and track the expression of certain genes. Fluorescence under certain light conditions, such as ultraviolet (UV) light, makes it apparent that the organism has incorporated and is expressing the desired genetic material. This method enables a clear visual confirmation of successful genetic engineering, which is essential for research and the development of transgenic plants and animals with desirable traits such as disease resistance, better nutritional value, and improved shelf-life.