Question

what is lichen
and
bionomial nomenclature
with example

Answer 1

Lichen is an indicator to find whether a solution is acid or base.
Binomial nomenclature is the scientific name of a species.
e.g.: Homo sapies scientific name of human.

Answer 2

lichen is a plant from which litmus is obtained
and
bionomial nomenclature is a process under which different species have given different names