Question

Many mammalian cells contain Thymidine Kinase, the mammalian enzyme uses the analogue _____ than does the viral enzyme.

(a) more efficiently

(b) less efficiently

(c) with same efficiency

(d) either with same or more efficiency

I have been asked this question during an internship interview.

The above asked question is from Cultured Cells in Mammals and Restricted Areas in Intact Organisms topic in section Using Other Organisms of Genetic Engineering

Answer 1

Correct answer is (b) less efficiently

To explain: Many mammalian cells contain thymidine kinase, the mammalian enzyme uses the analogue less efficiently than the viral enzyme. If cells lack viral enzyme they are resistant to analogue and are able to grow in a mammalian enzyme.