Raman scattering anisotropy of biological systems

Raman scattering from membranes, cells, and tissues must all be anisotropic, because the molecular orientations in these biological systems are anisotropic. How can such observed Raman scattering anisotropy be related with a biologically relevant molecular arrangement? This question is the subject of this paper. A general method of addressing this question will be given, with three examples illustrating the use of the method: (1) carotenoid arrangement in the eyespot of Chlamydomonas, (2) orientation of the tryptophan side chain in the coat subunit of a filamentous virus, and (3) polypeptide orientation in fowl feather barb.