Quantitative data on cell structure, shape, and size distribution are obtained by optical measurement of normal peripheral blood granulocytes and lymphocytes in a cell suspension. The cell nuclei are measured in situ. The distribution laws of the cell and nuclei sizes are estimated. The data gained are synthesized to construct morphometric models of a segmented neutrophilic granulocyte and a lymphocyte. Models of interrelation between the cell and nucleus metric characteristics for granulocyte and lymphocyte are obtained. The discovered interrelation decreases the amount of cell-nucleus size combinations that have to be considered under simulation of cell scattering patterns. It allows faster analysis of light scattering to discriminate cells in a real-time scale. Our morphometric data meet the requirements of scanning flow cytometry dealing with the high rate analysis of cells in suspension. Our findings can be used as input parameters for the solution of the direct and inverse light-scattering problems in scanning flow cytometry, dispensing with a costly and time-consuming immunophenotyping of the cells, as well as in turbidimetry and nephelometry. The cell models developed can ensure better interpretations of scattering patterns for an improvement of discriminating capabilities of immunophenotyping-free scanning flow cytometry.