Without a nucleus, multicellular life forms, called eukaryotes, would not exist. According to the Molecular Expressions , the nucleus acts as the administrative center and information processor for the cell by storing its genetic material and coordinating its activities.
Answer:- They are coelemate
-The body is covered with thin curticle
-They are triploblastic
-The have long and segment bodies
-Annelidas are bilaterally symmetrical
The answer is color.
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Malfunction might lead to organ diseases, and might alter the body metabolism.