Answer:

Explanation: Bone marrow is the spongy tissue that fills the cavities inside your BONES. Most of your blood cells are made in your bone marrow. The process by which blood cells are made is called haemopoiesis.

As an infant, haemopoiesis takes place at the centre of all bones. In later life, it is limited to the hips, ribs and breastbone (sternum). Some of you may have had a bone marrow biopsy taken from the bone at the back of your hip (the iliac crest).

You MIGHT like to think of the bone marrow as the blood CELL factory. The main workers at the factory are the blood stem cells. They are relatively small in number but are able, when stimulated, to reproduce vital numbers of RED cells, white cells and platelets. All blood cells need to be replaced because they have limited life spans.

There are two main families of stem cells, which DEVELOP into various types of blood cells.

Myeloid (‘my-loid’) stem cells develop into red cells, white cells (neutrophils, eosinophils, basophils and monocytes) and platelets.

Lymphoid (‘lim-foid’) stem cells develop into two other types of white cells called T-cells and B-cells.