What is the cell theory?

The scientific hypothesis that all living entities are made up of cells as the lowest functional unit is known as cell theory. According to cell theory, living things are made up of one or more cells, that the cell is the fundamental unit of life, and that new cells develop from existing cells. During cellular division, cells send genetic material to daughter cells. In terms of chemical makeup, all cells are fundamentally the same. Within cells, energy flow (metabolism and biochemistry) happens.

phylogenetic tree is the tree of life or evolution tree. it shows the different branches of evolution. the sequence goes like tissues - coelom - backbone - endoskeleton - segmentation

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