What is bone marrow

Bone marrow is a relatively important component of the human body and is also a part that is of decisive significance to human health. The main function of bone marrow is hematopoiesis. If there is an abnormality in the bone marrow, there will inevitably be certain problems with human health. Bone marrow is generally divided into red bone marrow and yellow bone marrow. Below, we will give you a detailed introduction to the definition, function and classification of bone marrow.

I. Definition

Bone marrow is a spongy tissue that exists in the medullary cavity of long bones (such as humerus and femur), the cancellous interosseous mesh of flat bones (such as ilium and ribs) and irregular bones (sternum, spine, etc.). The bone marrow that can produce blood cells is slightly red and is called red bone marrow. The bone marrow in some bone marrow cavities of adults contains many fat cells, is yellow in color, and cannot produce blood cells. This is called yellow bone marrow. When a person is born, the bone marrow cavity throughout the body is filled with red bone marrow. As age increases, the number of fat cells in the bone marrow increases, and a considerable portion of the red bone marrow is replaced by yellow bone marrow. Finally, red bone marrow is almost only found in the flat cancellous bones. This change may be because adults do not need all of the bone marrow cavity hematopoiesis, and partial bone marrow cavity hematopoiesis is sufficient to replenish the required blood cells. When the body is severely ischemic, part of the yellow bone marrow can be transformed into red bone marrow and restore its hematopoietic ability.

2. Function

The blood components in the human body are in a constant metabolism. Old cells are cleared and new cells are generated. The important function of the bone marrow is to produce stem cells that generate various cells. These stem cells differentiate and regenerate various blood cells such as red blood cells, white blood cells, platelets, etc. Simply put, the function of the bone marrow is hematopoietic function. Therefore, bone marrow is very important for maintaining the body's life and immunity.

3. Classification of Bone Marrow

Bone marrow is a spongy tissue that exists in the medullary cavity of long bones (such as humerus and femur), the cancellous interosseous mesh of flat bones (such as ilium and ribs) and irregular bones (sternum, spine, etc.). The bone marrow that can produce blood cells is slightly red and is called red bone marrow.

Yellow bone marrow is mainly fatty tissue, which can be converted into red bone marrow when the body is anemic. Some drugs, such as chloramphenicol and furans, can affect bone marrow hematopoietic function and cause aplastic anemia after long-term and excessive use.