A precursor cell in the bone marrow gives rise to which of the following?

A precursor cell in the bone marrow gives rise to which of the following?

• A. Osteocytes
• B. Osteoblasts
• C. Platelets
• D. Osteoclasts

Answer: (C)

Platelets come from megakaryocytes in the bone marrow. Hematopoietic stem cells differentiate into megakaryocytes, which mature and extend cytoplasmic projections into the blood vessels; pieces of these projections break off to form platelets. Platelets are essential for clotting, and they are cytoplasmic fragments rather than whole cells. In contrast, osteoblasts build bone, osteocytes are mature bone-embedded cells, and osteoclasts, derived from the monocyte lineage, resorb bone. Therefore, the precursor in the marrow gives rise to platelets.

Platelets come from megakaryocytes in the bone marrow. Hematopoietic stem cells differentiate into megakaryocytes, which mature and extend cytoplasmic projections into the blood vessels; pieces of these projections break off to form platelets. Platelets are essential for clotting, and they are cytoplasmic fragments rather than whole cells. In contrast, osteoblasts build bone, osteocytes are mature bone-embedded cells, and osteoclasts, derived from the monocyte lineage, resorb bone. Therefore, the precursor in the marrow gives rise to platelets.