Question

1. what is the name of the stem cell that gives rise to all formed elements; 9. what property of rbcs dooms them to a limited life span of about 120 days? 10. how is the production of platelets different from that of all other formed elements? pg. 347 hemostasis

Explanation:

1. Hematopoietic stem cells (HSCs) are responsible for giving rise to all formed elements in the blood, including red - blood cells, white - blood cells, and platelets.
2. Red blood cells (RBCs) lack a nucleus and most organelles. This lack of a nucleus and organelles means they cannot repair themselves, leading to a limited lifespan of about 120 days.
3. Platelets are produced by megakaryocytes through a process of fragmentation. Unlike other formed elements that are produced through typical cell - division and differentiation pathways, platelets are essentially cytoplasmic fragments of megakaryocytes.

Answer:

1. Hematopoietic stem cells
2. Lack of a nucleus and most organelles
3. Platelets are produced as cytoplasmic fragments of megakaryocytes while other formed elements are produced through typical cell - division and differentiation.