Which two parts typically make up a long bone in an adult?

Long bones in adults are primarily made up of two main parts: the diaphysis and the epiphysis. The diaphysis is often referred to as the shaft of the bone, which is the elongated central part that provides structural support and strength. The epiphyses are the ends of the bone, which are typically wider than the shaft and are involved in joint formation and articulation with other bones. This structure plays a crucial role in the distribution of weight and in facilitating movement.

The use of the terms "ends" for the epiphyses and "shafts" for the diaphysis accurately describes the essential components of long bones and highlights their functionality within the skeletal system. Understanding this division helps in comprehending how long bones grow, how they respond to mechanical stress, and their overall role in locomotion and support.