Stem cells in the bone marrow
- Examples of distinct types of differentiated cell that arise from a common stem cell within bone marrow include:
- erythrocytes
- neutrophils
- Stem cells in bone marrow are multipotent adult stem cells
Erythrocytes
- Erythrocytes are red blood cells, specialised to aid oxygen transport around the body
- Red blood cells lack a nucleus so they cannot perform mitosis to give rise to new cells; this means that new erythrocytes develop from bone marrow stem cells in order to maintain the red blood cell count in the blood
- The process by which erythrocytes arise from stem cells includes changes such as:
- loss of the nucleus
- a shape change to form a biconcave disc
- increased production of haemoglobin protein
- an increase in membrane flexibility
Stem cells in bone marrow differentiate to give rise to erythrocytes
Neutrophils
- The same stem cells that form erythrocytes also give rise to neutrophils, a type of white blood cell that is specialised to destroy pathogens by phagocytosis
- Changes that occur as stem cells differentiate into neutrophils include:
- indentations form in the nucleus, giving it a lobed structure
- production of hydrolytic enzymes increases
- lysosomes that contain hydrolytic enzymes accumulate
- membrane flexibility increases