Final answer:
The diaphysis is the central long region of a bone made up of compact bone, while the epiphyses are the ends of the bone that contain spongy bone.
Step-by-step explanation:
The diaphysis is the long region of the bone comprised mostly of compact bone. The epiphyses are the shorter ends of the bone comprised most of spongy bone. The walls of the diaphysis are composed of dense and hard compact bone, whereas the epiphyses are filled with spongy bone and often contain red marrow. Compact bone is structured into units called osteons and provides strength and support for the skeletal structure. Spongy bone, made of tiny plates called trabeculae, supports shifts in weight distribution and contributes to the resilience of the bone.