Most radiosensitive cell is: March 2009

Ans. B: Lymphocyte Radiosensitivity is the relative susceptibility of cells, tissues, organs, organisms, or other substances to the injurious action of radiation. In general, it has been found that cell radiosensitivity is directly propoional to the rate of cell division and inversely propoional to the degree of cell differentiation. In sho, this means that actively dividing cells or those not fully mature are most at risk from radiation. The most radio-sensitive cells are those which: Have a high division rate Have a high metabolic rate Are of a non-specialized type Are well nourished. - Highly sensitive-Lymphoid organs, bone marrow, blood, testes, ovaries, intestines - Low sensitivity-Muscle, brain, spinal cord Lymphocytes are most radiosensitive and platelets are more radioresistant.