We present the theory for a long polymer rod immersed in a nematic environment and find the effects of a nematic solvent on small fluctuations of the tangent vector perpendicular to the rod axis. We are thus able to calculate the physically interesting properties associated with our combined polymer and nematic system. These include tangent-tangent correlation functions and the scattering structure factor, which reproduces known qualitative experimental results rather well. As one biological application of our model, we analyze the possible effects of a weak nematic solvent on the mechanical properties of individual hemoglobin fibers. As another biological application, we model the effects of a strong nematic environment, provided by fd. virus, on the elastic and conformational properties of wormlike micelles. The work presented here can be viewed as constituting a microscopic model derivation of previous, more phenomenologically inspired, theories that deal with similar polymer/nematic systems. Interestingly, we find that a simple boundary condition of the nematic order at the rod surface agrees well with available experimental data.