Video Transcript
Which of the following would be an example of an organism modified by genetic engineering? (A) Cows that produce large amounts of milk and have high fertility were selected to breed over cows that do not to create modern dairy cows. (B) Golden rice is produced by inserting the gene for vitamin A production into the genome of common rice strains. (C) Pugs with a small body and flat face were bred together to make characteristics that were more desired by humans. Or (D) legumes, like peas and beans, have nitrogen-fixing bacteria on their roots, which helps increase soil nitrogen.
To answer this question, we need to understand the difference between genetic engineering and selective breeding. Let’s first remove the answer choices so we have more room to work with. Genetic engineering is the artificial manipulation of an organism’s genome using biotechnology. The genome refers to the complete set of genetic information in an organism. So, for example, if we had this wheat plant here and we wanted it to be resistant to insects, we can artificially introduce a gene for insect resistance into the wheat plant’s genome. This is genetic engineering because we’re modifying the DNA of the wheat plant artificially.
On the other hand, we can use selective breeding to introduce the insect resistance trait. Selective breeding involves choosing parents with desirable traits and breeding them in the hope that the offspring will carry those desirable traits. So here we would select another related plant that has insect resistance to breed with this plant. After multiple generations of breeding, we might be successful and introduce the trait. There is no artificial manipulation of the organism’s genome here. Now let’s go back to the answer choices and see which one best fits our definition for genetic engineering.
Answer choice (A) states that cows that produce large amounts of milk and have high fertility were selected to breed over cows that do not to create modern dairy cows. This is not an example of genetic engineering because there’s no artificial manipulation of the cows’ genome. In fact, this is a good example of selective breeding. Answer choice (B) states that golden rice is produced by inserting the gene for vitamin A production into the genome of common rice strains. This is an example of genetic engineering because the gene for vitamin A production was inserted into the genome of the rice plant. Although this seems to be the correct answer, let’s look at the other choices to be sure.
Answer choice (C) states that pugs with a small body and flat face were bred together to make characteristics that were more desired by humans. This is again an example of selective breeding and not genetic engineering. Answer choice (D) states that legumes, like peas and beans, have nitrogen-fixing bacteria on their roots, which helps increase soil nitrogen. This is neither selective breeding nor genetic engineering since it is simply a statement about a characteristic of the plant rather than any modifications that might be introduced through genome modification or breeding. Therefore, an example of genetic engineering is given by answer choice (B). Golden rice is produced by inserting the gene for vitamin A production into the genome of common rice strains.
