What best describes a transgenic animal?

• A. Animal with genes from an external source
• B. Animal which has an abnormal number of chromosomes
• C. Animal which has been transferred as an embryo to a foster mother
• D. Animal in which the cells of the gonads have undergone a mutation

Answer: (A)

Transgenic refers to an animal that carries genes from an external source integrated into its genome, so new genetic material is present and can be inherited. This distinguishes it from chromosomal abnormalities like having an abnormal number of chromosomes, which is a different type of genetic issue. It’s also different from embryo transfer, which is a reproductive technique rather than a genetic modification, and from a mutation in the gonads, which involves changes to the animal’s own genes rather than the introduction of foreign DNA.