2. A student investigated different types of white blood cells in the laboratory. Cell X' stains dark red and was found to contain two lobed nucleus. Cell Y'appeared purple in colour, when stained with Leishman's stain. Large granules are also seen in the cytoplasm under a microscope. The third cell, ‘Z was observed to be multinucleated. Its cytoplasm is filled with very fine granules. In the above investigation, the cell X, Y and Z can be identified as A. monocyte, lymphocyte and basophil respectively. B. basophil, eosinophil and monocyte respectively. C. lymphocyte, neutrophil and eosinophil respectively. Deosinophil, basophil and neutrophil respectively.
Answers
Explanation:
addition to their distinctive cytochemical staining characteristics, blood cells can be distinguished on a gross level by their average size and granularity as measured by flow cytometry. With a flow cytometer, the optical effects of passing a single cell through a laser light beam can be measured in terms of light scattered by the cell in two directions -- parallel to the beam ("forward scattering" or FSC) and perpendicular to the beam ("side scattering" or SSC). Greater FSC correlates with larger cell size while greater SSC correlates with more granularity in the cytoplasm and nucleus of a cell. A two-dimensional plot of FSC versus SSC for human blood cells, reveals that different cell types exhibit distinct average ranges of size and granularity. Thus, flow cytometry can be used to analyze and even physically isolate different blood cell populations.
With a modified flow cytometer designed to detect fluorescent light stimulated by the laser beam, i.e., a fluorescence-activated cell sorter (FACS), even finer distinctions between different cell populations can be made if they have been treated with fluorescently tagged monoclonal antibodies directed against specific cell surface molecules, generically referred to as cluster of differentiation (CD) antigens.