bone marrow

Introduction

Soft connective tissue which occupies the medullary cavity of long bones, the larger central canals & all of the spaces between trabeculae of spongy bone. It consists of delicate reticular connective tissue containing hematopoietic cells (red marrow) or adipose tissue (yellow marrow).

Red marrow is restricted to the vertebrae, sternum, ribs, cranial bones, & epiphyses of long bones. It is the main hematopoietic organ in the adults. Hematopoietic cells & variable numbers of adipocytes are present.

Yellow marrow may revert to red marrow.

More general terms

• extracellular compartment (extracellular space)

Additional terms

• bone marrow aspirate
• bone marrow biopsy
• bone marrow disease
• bone marrow transplantation (BMT)