The medullary cavity is the bone marrow cavity contains red and/or yellow bone marrow; red bone marrow is the site of hematopoiesis. The end of a long bone is known as the epiphysis. Compact bone (cortical bone) is the dense outer layer of bone. The diaphysis is the shaft of a long bone.

Metaphysis: has the greatest metabolic activity, and contains the epiphyseal plate, which is replaced by the epiphyseal line

Diaphysis: mechanical support, site of bone marrow and muscle attachments

Apophysis: functions as a site for attachments of ligaments and tendons

Epiphysis: at the end of long bones

Periosteum: covers the diaphysis and parts of metaphysis. 

Bone growth has multiple steps that allow growth in both length and width. One thing to remember is the functions of the bone cells during growth and development. Osteoclasts are responsible for "hollowing out" the center of long bones, which makes for larger cavities within the diaphysis. Osteoblasts, on the other hand, are responsible for laying down additional bone matrix on the outsides of the bones.

As bone cells mature, they become further embedded within subsequent layers of the bony matrix. Osteogenic cells, which give rise to osteoblasts, are located in the outer periosteum of the bone. When damage occurs to the bone, osteogenic cells differentiate and begin repairing the bony matrix from the outside.

Bone is a dynamic tissue that remodels under mechanical stress, or orthodonture. Mechanical stress in bone generates electric potential via the piezoelectric effect. Negative potential results in bone deposition (bone is laid down) whereas positive potential results in bone resorption (bone is broken down).

Histologically, the epiphyseal growth plate is divided into five zones. From epiphysis to diaphysis they are the resting zone, zone of proliferation, zone of maturation, zone of calcification, and zone of ossification. At the growth plate, cartilage is constantly being developed into the bone of the diaphysis. The stages of this process align with the regions of the epiphyseal plate. The resting zone houses quiescent chondrocytes that are not yet active in bone synthesis. The zone proliferation is characterized by chondrocyte mitosis and replication. These cells then develop and grow with in the zone of maturation. Eventually the cells reach their maximum growth and undergo apoptosis to release cell contents in the zone of calcification. This prevents cartilage from infiltrating the bony region of the diaphysis. The chondrin matrix begins to calcify in this zone as well. As calcification progresses and the organic cartilage matrix is replaced by bony hydroxyapatite mineral in the zone of ossification, the epiphyseal plate completely replaces the original chondrocytes with bone.

As more bone is produced, the epiphyseal plate is pushed farther and farther away from the midpoint of the bone. The lengthening of the bone ends when the zones of the epiphyseal plate fuse and further growth becomes impossible.

There are three primary types of bone cell: osteoblasts, osteocytes, and osteoclasts. Osteoblasts are responsible for creating new bone by sequestering minerals and generating new hydroxyapatite matrix. Osteoclasts break down this matrix, releasing the minerals into the blood. Osteocytes are mature osteoblasts that have become embedded in the matrix of the bone and serve primarily for communication purposes.

Satellite cells are located at the periphery of muscle cells and are capable of dividing and giving rise to new myoblasts. Satellite cells are, essentially, adult muscle stem cells. Common lymphoid progenitor cells are another type of adult stem cell, housed in red bone marrow, and are responsible for regenerating the erythrocyte population of the body, as well as producing lymphocytes.

There are five classifications of bone in the body: long, short, flat, irregular, and sesamoid. The sternum, as well as many of the bones in the skull, are examples of flat bones.

Long bones have a greater length and diameter, while short bones have similar length and diameter measures. The femur is a long bone, while the carpals are short bones. Short bones generally appear square. Irregular bones have unique shapes, such as the sphenoid and ethmoid. Sesamoid bones are generally round and are embedded in tendon structures. The patella is a sesamoid bone.

The five types of bones are flat bones, short bones, long bones, irregular bones, and sesamoid bones. Flat bones are found in the skull, and contain suture joints that fuse together as a developing child ages. The frontal, temporal, parietal, and occipital bones are all flat bones. Within the interior skull structure, the ethmoid and sphenoid bones are considered irregular bones.

The five types of bones are long bone, short bone, irregular bone, flat bone, and sesamoid bone. Irregular bones are categorized by a shape that does not fit into the other categories. Typical vertebrae do not fit into any geometric shape.

Ribs are considered flat bones. Flat bones are generally thin and flat, and can frequently be wide and/or curved. The ribs, sternum, and scapula are considered flat bones.

Long bones are classified as bones with a length that is substantially greater than their width, such as the femur, radius, and phalanges. Short bones, in contrast, have similar length and width measurements, such as the carpals and tarsals. Sesamoid bones are embedded in tendons, such as the patella. Intrasutural bones (or Wormian bones) are found between the primary bones of the skull in abnormal cases of suture formation during development.