White blood cell chasing and consuming a bacterial organism through a process called phagocytosis.

White blood cell chasing and consuming a bacterial organism through a process called phagocytosis.

Explained simple phagocytosis is the process of a cell eating. The ability to hunt down and eat "food" was a huge accomplishment for cells. Once the process was refined, unicellular organisms became able to eat other objects that were almost as big as they were. They were also able to become independent of processes like diffusion and active transport. Overall, cells could grow faster and larger. That faster growth meant it would take less time for the cell to reproduce. 

Know more: https://en.wikipedia.org/wiki/Phagocytosis