In general, the process responsible for the growth and repair of human tissue is the healing process, which takes place in three phases.
1. inflammatory response. Injured tissues release chemicals that draw resources to the area, alert the body that damage has occurred and inhibit function to prevent further injury.
2. Repair phase. Once injured area is walled off and debris removed, construction to replace or repair injured tissue begins. New blood vessels grow in the injured area maximizing transport within tissue.
3. Remodeling phase. Construction of permanent tissue , typically strong scar tissue made from dense network of collagen fibers.
Looking at it from cell level, the process of mitosis is actually taking place during healing.
Mitosis is used for growth and repair and produces diploid cells identical to each other and to the parent cell.
New cells are needed throughout life. These are for growth and replacement of damaged or worn out tissue. The body obtains such through the process of mitosis.
The immune system, and the excretory system
(Honestly, all of them work to keep us 'healthy', but I believe these are the ones you're looking for)
