  Single molecule force spectroscopy provide details of the underlying energy
surfaces of proteins which are essential to the understanding of their
unfolding process. Recently, it has been observed experimentally that by
pulling proteins in different directions relative to their secondary structure,
one can gain a better understanding of the shape of the energy landscape. We
consider simple lattice models which are anisotropic in nature to study the
response of a force in unfolding of a polymer. Our analytical solution of the
model, supported by extensive numerical calculations, reveal that the force
temperature diagrams are very different depending on the direction of the
applied force. We find that either unzipping or shearing kind transitions
dominate the dynamics of the unfolding process depending solely on the
direction of the applied force.
