Final answer:
Satellite cells are stem cells in skeletal muscles activated to repair damaged tissue. They facilitate protein synthesis for regeneration but, if damage exceeds their repair capacity, fibrosis results in scar tissue formation, impairing muscle function.
Step-by-step explanation:
In skeletal muscle, stem cells known as satellite cells are located between the myocyte sarcolemma and the basal lamina. These cells are activated after injury and fuse with the damaged muscle cell to aid in repair.
Satellite cells are essential for muscle repair and regeneration. Although the number of muscle cells is generally fixed after development, these cells are instrumental when damage occurs. Residing just outside the sarcolemma, satellite cells spring into action following muscle injury. They are stimulated by growth factors released during muscle stress and proceed to grow, differentiating into myoblast-like cells. These cells then fuse with the injured muscle fibers, contributing their nuclei and aiding in the protein synthesis necessary for muscle repair and growth. However, their regenerative capacity is limited. Excessive damage beyond the repair capabilities of satellite cells leads to the formation of non-functional scar tissue through the process of fibrosis, resulting in loss of muscle strength and endurance.