Question

Which of the following correctly defines a transgenic animal?

• A. An animal which has foreign DNA and RNA in some of its cells because of an injection of DNA and RNA into the nucleus of the zygote from which it is developed
• B. An animal which has foreign DNA in all its cells because of an injection of DNA into the nucleus of the zygote from which it is developed
• C. An animal that has foreign DNA in some of its cells because of an injection of DNA into the nuclei of some of the cells of the blastocyst
• D. An animal which has foreign DNA in all its cells because of an injection of DNA into the nuclei of some of the cells in adulthood

Answer 1

The correct option is B An animal which has foreign DNA in all its cells because of an injection of DNA into the nucleus of the zygote from which it is developed

Animals that have had their DNA manipulated to possess and express an extra (foreign) gene are known as transgenic animals. The desired foreign genes can be introduced into fertilized eggs or embryos through microinjection. These transgenic eggs or embryos can be implanted into the uterus of another female, called surrogate mother for their further development. So, an animal which has foreign DNA in all its cells because of an injection of DNA into the nucleus of the zygote from which it is developed is true transgenic animal.