Diagram of a mature long bone

A mature long bone can be diagrammed as follows:

_______________
/ Endosteum \
/__________________\
/ Compact bone \
/______________________\
/ Spongy bone \
/___________________________\
/ | \
/ | \
/ | \
/ | \
/ | \
/ | \
/ | \
/ | \
Periosteum Epiphyseal Epiphyseal Periosteum
(Outer Layer) Line Line (Outer Layer)
| |
Red | Red |
Bone | Bone |
Marrow | Marrow |
| |
Articular Articular
Cartilage Cartilage
| |
| |
| |
Medullary Medullary
Cavity Cavity
| |
| |
Yellow Yellow
Bone Bone
Marrow Marrow

Key:
- Periosteum: Tough, fibrous layer covering the outer surface of the bone.
- Compact bone: Dense, hard bone tissue that forms the outer layer of most bones.
- Spongy bone: Porous, less dense bone tissue found within the ends of long bones and the middle of other bone types.
- Endosteum: Thin, delicate membrane lining the medullary cavity and trabeculae of spongy bone.
- Epiphyseal Line: Solid line in the long bone indicating where the growth plate (epiphyseal plate) once was.
- Red Bone Marrow: Soft, spongy tissue found inside spongy bone, responsible for blood cell production.
- Articular Cartilage: Smooth, slippery cartilage covering the ends of bones where they articulate with other bones.
- Medullary Cavity: Central cavity within the diaphysis (shaft) of the long bone, containing yellow bone marrow.
- Yellow Bone Marrow: Fatty tissue found in the medullary cavity, storing energy reserves.

Note: This diagram is a simplified representation of a mature long bone and does not include all the parts in their actual complexity and anatomical detail.