The outer surface (or portion) of bones is more dense or compact than
the inner portion. The inner structure (or portion) of a bone is more spongy
or cancellous.
The long bones are hollow, with dense or compact bone surrounding a
canal (marrow) that houses bone marrow. Bone marrow is the soft tissue in
the marrow cavities of many bones, especially the larger ones. You have two
types of bone marrow.
Bone TerminologyBODY SHAFT
The main portion of a bone.
CANAL
A passage through a bone, also called me-atus.
FORAMEN
A hole in a bone, generally for vessels or nerves.
PROCESS
An extension or projection from a bone.
TUBERCLE
A lump or hump in a bone.
HEAD
The end of a bone—enlarged and often rounded.
NECK
The tapered portion of a bone between the head and the shaft (body).
CREST
The prominent ridge of a bone.
RED BONE MARROW — Produces your red blood cells and B-
lymphocytes and other immune cells.
YELLOW BONE MARROW — Predominately fat that is stored for energy
needs.