After defining a Universe for computer science in opposition to the Universe of biology, this paper presents the roles that cellular division plays in both of them. Based on the nine construction rules of the so-called Tom Thumb algorithm, cellular division leads to a novel selfreplicating loop endowed with universal construction and computation. The self-replication of the totipotent cell of the "LSL" acronym serves as an artificial cell division example of the loop and results in the growth and differentiation of a multicellular organism.