<prompt> The outer covering of diatom is made of:MagnesiumSilicaHydrocarbonsNone  <response>: MEDICO-LEGAL SIGNIFICANCE OF DIATOMS TEST Diatoms are unicellular algae with silicaQin its cell wall Only a beating hea can transpo the diatoms to distant organs It indicates death due to drowningQ Diatoms in bone marrow and brain is more reliable than any other organ As diatoms resist putrefactionQ, it is valuable even in putrefaction Diatoms are negative in dead bodies thrown in waterQor dry drowningQ 