Tissue growth refers to the process by which cells multiply and increase in number, leading to the expansion of tissues in the body. This process is essential for development, healing, and maintenance of organs. Tissue growth can occur through two main mechanisms: hyperplasia, which is an increase in cell number, and hypertrophy, which is an increase in cell size. Various factors influence tissue growth, including hormones, nutrients, and genetic factors. For example, during childhood and adolescence, growth hormones stimulate tissue growth, while in adults, tissue repair and regeneration are crucial for recovery from injuries. Understanding tissue growth is important in fields like medicine and biology.