Scientists have used genetic engineering to protect tomatoes against the effects of freezing.科学家利用遗传工程保护番茄免受严寒天气的影响。The crops were made resistant to disease by genetic engineering.这些农作物通过遗传工程产生了抗病性。Genetic engineers transpose or exchange bits of hereditary material from one organism to the next.遗传工程师将某一生物的小段遗传物质调换到另一生物，或与其互换。