How can one cell become a multicellular organism

When the division of single cell occurs, two cells are formed and when again these two cells are pass through division process, it becomes 4 cells and so on. So according to the definition of multicellular organisms, those organism which contains more than one cell is known as multicellular organism. So we can say that every multicellular organism is made of a single cell.

the denominator has a very specific role.

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