What defines transgenic organisms?

• A. Organisms that have been bred for specific traits
• B. Organisms that contain DNA from another species
• C. Organisms altered by traditional breeding methods
• D. Organisms with naturally occurring mutations

Answer: (B)

Transgenic organisms are specifically defined by their genetic modification to include DNA from a different species. This means that through biotechnology, genes that carry desired traits from one organism can be inserted into another organism's genome, enabling it to express those traits. This process often involves using techniques such as recombinant DNA technology, where the gene of interest is isolated and then introduced into the target organism's cells.

The essence of a transgenic organism lies in the integration of foreign DNA, which distinguishes it from organisms that have simply been bred for specific traits through traditional means, as those do not involve the manipulation of genetic material across species boundaries. Furthermore, transgenic organisms are distinct from those altered by conventional breeding methods, as these methods rely on selective breeding of naturally occurring traits, rather than direct genetic engineering. Similarly, organisms with naturally occurring mutations do not qualify as transgenic since their changes have not involved introducing foreign genetic material. Thus, the defining characteristic of transgenic organisms centered on the incorporation of DNA from another species makes it clear why this answer is correct.