  The dielectric properties of single-shell spherical cells with an intrinsic
dielectric dispersion has been investigated. By means of the dielectric
dispersion spectral representation (DDSR) for the Clausius-Mossotti (CM)
factor, we express the dispersion strengths as well as the characteristic
frequencies of the CM factor analytically in terms of the parameters of the
cell model. These analytic expressions enable us to assess the influence of
various model parameters on the electrokinetics of cells. Various interesting
behaviours have been reported. We extend our considerations to a more realistic
cell model with a graded core, which can have spatial gradients in the
conductivity and/or permittivity. To this end, we address the effects of a
graded profile in a small-gradient expansion in the framework of DDSR.
