Which organ is the primary site of haematopoiesis in the foetus before mid-pregnancy?

Option 2 : Liver

Concept:

• Hematopoiesis -> is the formation of blood cells
• Red blood cell formation occurs in this process
• The primary site is the liver but it can even occur in the spleen and bone marrow
• The life span of RBC -> 120 days
• After every cycle it these RBC will be recycled in the spleen
• Spleen is considered as the graveyard of RBC

Explanation:

• Hematopoiesis occurs in the fetal liver and spleen
• Adults -> Bone marrow and thymus
• Extramedullary hematopoiesis = EH -> Hematopoiesis occurring in organs outside of the bone marrow
• Hematopoietic stem and progenitor cells in the fetal liver migrate to the bone marrow and the marrow becomes the major hematopoietic site after birth.

• Lung -> majorly responsible for respiration
• Bone -> marrow is responsible for blood cell production and support
• Liver -> Produces enzymes acts in many functions
• Spleen -> Graveyard of RBC