What characterizes a transgenic organism?

A transgenic organism is characterized by having genes that have been artificially introduced from other species into its genome. This process is typically achieved through genetic engineering techniques that allow for the insertion of specific genes to confer desired traits, such as disease resistance in plants or the production of therapeutic proteins in animals. The incorporation of foreign DNA can lead to new characteristics that are not found in the organism's ancestral lineage.

For example, a common transgenic plant is one that has been modified to express a gene from a bacterium that provides resistance to herbicides. This genetic modification allows the plant to survive applications of herbicides that would normally kill non-modified plants.

The other choices are not representative of transgenic organisms. Natural organisms do not have genes from unrelated species artificially inserted into their genomes. Additionally, many transgenic organisms are fully capable of reproduction, reproducing both sexually and asexually, depending on the species. Lastly, more than one cell type is not a definitive characteristic of transgenic organisms; many organisms, whether transgenic or not, consist of multiple cell types. The hallmark of transgenic organisms lies specifically in their genetic makeup, which is altered to include external genetic material.