Nondisjunction is the failure of homologous or sister chromatids to separate properly during cell division .There are 3 forms of non junctions.1)failure of a pair of homologous chromosome to separate in meisis 1
Not always, the toxins may have been absorbed by the body and released in urine
Prokaryotes reproduce by *BINARY FISSION* which creates *2*exact daughter cell clone(s) of the original parent cell.
Limestone.
It is a sedimentary rock composed of calcite and aragonite. It is used as a building material mainly because it is easily available and easy to work with.
Limestone is used in the manufacture of steel as it is the primary raw material that helps to remove impurities from the iron ore and produces waste matter that has low melting point and viscosity
