Which bone marrow cell type gives rise to platelets?

Which bone marrow cell type gives rise to platelets?

• A. Eosinophil
• B. Lymphocyte
• C. Platelets
• D. Megakaryocyte

Answer: (D)

Platelets come from megakaryocytes in the bone marrow through a process called thrombopoiesis. A megakaryocyte is a large marrow cell that becomes polyploid and extends long cytoplasmic extensions into the blood vessels; these extensions break up into platelets that enter the circulation. This makes megakaryocytes the source of platelets. Eosinophils and lymphocytes belong to different hematopoietic lineages (granulocytes and lymphoid cells, respectively) and do not produce platelets. Platelets themselves are cytoplasmic fragments, not cells that generate others.

Platelets come from megakaryocytes in the bone marrow through a process called thrombopoiesis. A megakaryocyte is a large marrow cell that becomes polyploid and extends long cytoplasmic extensions into the blood vessels; these extensions break up into platelets that enter the circulation. This makes megakaryocytes the source of platelets. Eosinophils and lymphocytes belong to different hematopoietic lineages (granulocytes and lymphoid cells, respectively) and do not produce platelets. Platelets themselves are cytoplasmic fragments, not cells that generate others.