Is it farther or further?
cytophotometry cy·to·pho·tom·e·try (sī'tə-fō-tŏm'ĭ-trē)
The study of cells and chemical compounds within cells by means of a cytophotometer.
cytophotometer cy·to·pho·tom·e·ter (sī'tō-fō-tŏm'ĭ-tər)
An instrument used to determine the identity and location of the chemical compounds within a cell by measuring the intensity of light passing through stained sections of the cytoplasm.