Final answer:
The epiphyseal plate allows for longitudinal bone growth in long bones through a process of continuous cartilage formation and ossification, which ceases in early adulthood when the plate is replaced by bone.
Step-by-step explanation:
The epiphyseal plate is critical for the longitudinal growth of long bones in the body. It is a layer of hyaline cartilage located at the ends of long bones, where new cartilage is continuously formed and then ossified, contributing to the increase in length of the diaphysis. This process is part of endochondral ossification—a complex sequence of events involving cartilage matrix mineralization, chondrocyte proliferation, cell death, and replacement by bone tissue, which is regulated by growth hormones.
The epiphyseal plate is composed of four distinct zones, each serving a specific role in bone growth. Once a person reaches early adulthood, the epiphyseal plate is replaced by bone, leaving a remnant known as the epiphyseal line, signaling the end of bone lengthening.