Bone: the organ - components

Grossly, the bone tissue has two different appearances: compact and spongy. Compact (cortical) bone appears as a solid mass to the naked eye. This bone comprises the shafts of long bones and forms a peripheral layer over all bones, except in regions of articular cartilages. Spongy (cancellous) bone is found in the interior and resembles a sponge to the naked eye. It consists of a network of bony spicules or trabeculae, enclosing small marrow spaces. Spongy bone is present in the epiphyses and lining the interior of the diaphysis. 1x, 10x

Grossly, the bone tissue has two different appearances: compact and spongy. Compact (cortical) bone appears as a solid mass to the naked eye. This bone comprises the shafts of long bones and forms a peripheral layer over all bones, except in regions of articular cartilages. Spongy (cancellous) bone is found in the interior and resembles a sponge to the naked eye. It consists of a network of bony spicules or trabeculae, enclosing small marrow spaces. Spongy bone is present in the epiphyses and lining the interior of the diaphysis. 1x, 10x

Red marrow fills the spaces between spicules of spongy bone in the epiphyses of adults and is also present in the marrow cavity of younger individuals, as shown here. Red marrow consists of myeloid, (hemopoietic) tissue that produces red and white blood cells.

Yellow marrow, composed of adipose tissue, replaces red marrow and fills the shafts of adult long bones. Marrow tissue was not preserved in the dried specimen.