We directly visualize single polymers with persistence lengths ranging from
ℓp=0.05 to 16 μm, dissolved in the nematic phase of rod-like {\it fd}
virus. Polymers with sufficiently large persistence length undergo a coil-rod
transition at the isotropic-nematic transition of the background solvent. We
quantitatively analyze the transverse fluctuations of semi-flexible polymers
and show that at long wavelengths they are driven by the fluctuating nematic
background. We extract both the Odijk deflection length and the elastic
constant of the background nematic phase from the data.Comment: 4 pages, 4 figures, submitted to PR