Nucleotides can be radiolabelled before they are incorporated into newly forming DNA and, therefore, can be assayed to track their incorporation. In a set of experiments, a student-faculty research team used labelled T nucleotides to study the incorporation of labelled nucleotides into a culture of lymphocytes. They found that the lymphocytes incorporated the labelled nucleotide at a significantly higher level after a pathogen was introduced into the culture. What might they conclude from this observation?
A) The pathogen consumed radiolabelled nucleotides.
B) Infection causes lymphocytes to divide more rapidly.
C) Infection causes lymphocytes to increase in size.
D) Infection causes lymphocyte cultures to skip some parts of the cell cycle.

Question

Quizplus · Accepted Answer

The higher level of incorporation of labelled nucleotides suggests that lymphocytes were dividing more rapidly, likely in response to the pathogen. The other options do not explain why there would be an increase in nucleotide incorporation.

Nucleotides Can Be Radiolabelled Before They Are Incorporated into Newly