How do organisms grow and repair themselves?

Organisms grow and repair themselves through a process called cell division.

Cell as per definition is the building block of life, not only in humans but also for all other living organisms. Thus, every cell is important to every form of life in the planet.

During cell division, cells divide themselves and make new cells. When a certain part of the body is damaged, say, you bite your lip accidentally, in a matter of days or so, the wound heals. How? The cells communicate with each other when performing cell division through chemical signals. The new cells formed after cell division replenishes the old cells, thus, healing your wounds faster.