What is a structure within a bone contains cartilage cells that divide and increase the size of the bone until adulthood?

The structure within a bone that contains cartilage cells responsible for dividing and increasing the size of the bone until adulthood is called the epiphyseal plate, or growth plate. This plate is composed of hyaline cartilage and is located at the ends of long bones. During childhood and adolescence, the cartilage cells proliferate, allowing for lengthening of the bone, which eventually ossifies and stops growing once adulthood is reached.