Nucleotides can be radiolabeled before they are incorporated into newly forming dna and, therefore, can be assayed to track their incorporation. in a set of experiments, a studentfaculty research team used labeled t nucleotides and introduced these into the culture of dividing human cells at specific times. the research team used their experiments to study the incorporation of labeled nucleotides into a culture of lymphocytes and found that the lymphocytes incorporated the labeled nucleotide at a significantly higher level after a pathogen was introduced into the culture. they concluded that

The four nitrogenous bases that are present in DNA are adenine, guanine, thymine and cytosine. These nucleotides can be radiolabelled before the new DNA forms and the composition of specific nucleotide of DNA can be estimated.

During the experiment, research team found that the incorporation of radioactive nucleotides composition increase after the introduction of pathogen in the culture. This means that the cell starts producing more number of cell to fight against the pathogen. The infection of pathogen is mainly responsible for the division of lymphocytes more rapidly.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.

yes it is weird but true