Diaphysis

Definition

The diaphysis is the central, elongated shaft of a long bone. It is primarily composed of compact bone and contains the medullary cavity filled with yellow marrow.

5 Must Know Facts For Your Next Test

1. The diaphysis provides strong support without cumbersome weight.
2. It houses the medullary cavity which stores yellow marrow for fat storage.
3. Compact bone in the diaphysis makes it dense and capable of withstanding stress.
4. Blood vessels and nerves run through the diaphysis via the nutrient foramen.
5. Osteocytes within the diaphysis maintain the mineral content of bones.

Review Questions

• What type of bone tissue primarily composes the diaphysis?
• What is stored in the medullary cavity of the diaphysis?
• How does the structure of the diaphysis contribute to its function?

Related terms

epiphysis: The rounded end part of a long bone, typically wider than the shaft.

metaphysis: The narrow zone between the epiphysis and diaphysis where growth occurs during development.

periosteum: A dense layer of vascular connective tissue enveloping bones except at the surfaces of joints.