Red bone marrow is primarily located in flat bones (such as the sternum and pelvis) and in the epiphyses of long bones. It is responsible for producing red blood cells, a process known as erythropoiesis. At birth, all bones of the human skeleton carry out erythropoesis, but many bones stop this function as the newborn ages.

It is important to note that yellow bone marrow is found in the medullary cavity within the diaphyses of long bones and assists in fat storage.

Red bone marrow is filled with hematopoietic stem cells. Red bone marrow is found in the heads, or epiphyses, of long bones. Yellow marrow fills the medullary cavity and consists mostly of fats. The diaphysis contains the medullary cavity and therefore contains no red marrow. The periosteum has no marrow in it at all.

Since red bone marrow is a site of red blood cell and platelet production, hypoxia (low oxygen) would result in an increase in red marrow and therefore RBC concentration.  Yellow bone marrow (typcially adipocyte-filled) can be converted into red bone marrow under conditions of low oxygen or blood loss.  

Bone is living tissue and it therefore requires a blood supply, which is brought to the bone itself by the vital soft tissue envelope around it. Articular cartilage routinely caps the epiphysis (end) of a long bone. The region adjacent to the epiphysis is termed the metaphysis, whereas the shaft of a long bone is the diaphysis.  

There are two main types of structural configurations that form bone tissue: compact bone (or cortical bone) and spongy bone (or cancellous bone). Compact bones function to maintain the structure of the body and release chemical elements, such as calcium. Compact bones are characterized by their specialized haversian system, or osteon structure. It is the fundamental unit of compact bone structure and consists of a haversian canal (a tunnel that is created by osteoclast activity to remove bone tissue) and lamellae (layers of compact bone tissue organized in concentric circles). Spongy bones do not contain these haversian systems.

Spongy bone is relatively flexible bone tissue that is found at the end of long bones (the epiphyses). One of their main functions is to develop red blood cells, as they house the red bone marrow responsible for erythropoiesis and erythrocyte maturation. Compact bones, on the other hand, contain yellow bone marrow that functions to store fat and adipose tissue.

Osteocytes are differentiated osteoblasts that have become imbedded in hydroxyapatite bone matrix. The osteocytes are found in small gaps in bone matrix called lacunae and exchange nutrients with the blood using small canals called canaliculi. Lamellae are the concentric regions of osteocytes that are arranged around the central Haversian canal. The canal houses blood vessels and nerves to nourish and stimulate the osteocytes via the canaliculi.

The skeletal system is responsible for a variety of functions in the body. Long bones contain both red and yellow bone marrow, which are the sites for fat storage and hematopoeisis respectively. Bones are also responsible for the storage of calcium and phosphate, which can be released in order to maintain normal levels in the blood.

White blood cells are derived from stem cells in the bone marrow. B-cells continue to develop in the bone marrow, but T-cells develop in the thymus.

Bone matrices store these slightly soluble calcium salts so that they can be released into the bloodstream in times of low blood calcium levels. As a result, these salts are an example of how the skeletal system provides mineral storage for the body.

Movement and bone cell production are also primary functions of the skeletal system, but are not linked to calcium salts. Energy storage is linked to the fats stored in the yellow marrow of the bone.

When it comes to the strength and resilience of bone, both collagen and calcium play important roles. Collagen provides bones with great tensile strength, and calcium (usually in the form of hydroxyapatite) provides bones with great compressive strength. In the event of a calcium deficiency, weight placed on bones would cause them to bend irregularly, resulting in the characteristic bending of bones found with rickets.

A deficiency in collagen would cause damage to the bone during extension or stretching forces. Bone marrow does not play an important structural role, and is more important for bone function.

Bone consists of calcium-phosphate crystals, known as hydroxyapatite, in a collagen matrix. The molecular formula for hydroxyapatite is . Collagen's structure depends on hydroxylysine and hydroxyproline for stability. Potassium is not required in bone.

While these specific formulas are not generally tested knowledge, it is important to know what molecules may influence bone composition and growth.