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.

answer: decrease

a limiting factor is the one which decrease the abundance, distribution and causes extinction of the population of species in a ecosystem. here, predators including hawks, owls and snakes are the limiting factor for the population of mexican free tailed bat.   although bats are nocturnal animals as they forge for food at night these predators also may remain active during night which can decrease the population of the mexican free-tailed bats. also, these bats eat only one type of insects that are moths. the food can also be a limiting factor as all 400 members are dependent upon same type of food needs that are moths. the decrease in the moth population can cause decrease in population size of the mexican free-tailed bats.

therefore, the scenarios will most likely to decrease the population size of the mexican free-tailed bats.