EFFECT OF HEAVY-METAL COMPOUNDS ON NUCLEOLUS OF ROOT MERISTEMATIC CELLS OF PISUM-SATIVUM L

Visualisation of one or more nucleoli in eukaryotic cell attracted the attention of early cytologists and by the end of 19th century a relat ionship between the size of the nucleus and the synthetic activity of the cell was postulated. In the present investigation, due to the effe cts of heavy metal compounds like Mercuric chloride, Cadmium chloride, Lead nitrate on Pisum sativum L for different concentrations and dura tions nucleolar shape, size and number was altered with the size of th e nucleus. These alterations follow the previous reports on the other plant and animal system where the experimental evidences indicate the reducing activity of rRNA and protein synthesis.