This paper is an analysis of educational materials produced by the United Kingdom's Medical Research Council (MRC). While the MRC's Research Updates are designed to be used in the classroom, interviews with MRC contributors to the Updates and with teachers and students show that their function is complex. Drawing on these data, we point to three facets of biomedical texts that have been neglected. First, we note that these texts are meant to influence only a proportion of their target audience. Their impact is to set up a 'resonance' in this proportion of students, a resonance that will at some point in the future materialise as a choice to pursue a career in biomedical research. This is our second observation: that texts are designed to have a latent effect. These texts also address another audience - government bodies who demand that the MRC engage in educational and public understanding of science activities. As such, and this is our third observation, scientific texts can signify laterally, not to readers directly engaged with them, but to observers whose concern is with their trajectory.