Question

In the absence of microorganisms the earth would become a heap of dead plants and animals justify this statement

Answer 1

heya as these microbes are the DECOMPOSERS So they are essential for the decomposition and conversion of the dead remains of plants and animals into the basic elements of which they are made of .

Answer 2

yes the statement is true .

because any living organisms such as the animals or plants have to end .
any food chain of the envirnoment end with micro organisms or the decomposers because they decompose all the the dead things
so the micro organisms decompose that things and then convert that material into soil. or mixed into soil.
so with the presence of the micro organisms the every dead material get mix into soil and the balance of the envirnoment remains same.
so if the micro organisms are absence on the earth every dead material cant decompose and the dead material remains on the earth in the large quantity without mixing with soil.
all the dead materials remains on earth in large quantity and the earth looks like heap of the dead plants and animals.

hope it helps!!!