Some bed bugs had mutations in their genetic code which allowed them to survive the chemical pesticide and they produced chemically resistant offspring. How can this be explained?

Ifound this information on google “yes. they have a mouth and brain at one end and an anus at the opposite end. what characteristics distinguish an annelid from other worms? annelids have segmented bodies and a coelem which is a tube filled with fluid and contains most of the organs.“ i hope it you

Where are the phrases

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