megakarüotsüüt

Megakarüotsüüdid are very large cells found in the bone marrow. They are precursors to platelets, which are tiny cell fragments essential for blood clotting. These cells are characterized by their unusually large size and a multi-lobed nucleus. The cytoplasm of a megakaryocyte is abundant and granular, containing the internal structures that will eventually form platelets. Megakaryocytes originate from hematopoietic stem cells, undergoing a process of differentiation and maturation. This process involves endomitosis, where the cell replicates its DNA without dividing, leading to a polyploid nucleus and increased cell volume. The cytoplasm then fragments into proplatelets, which are then released into the bloodstream and further break down into individual platelets. The production of megakaryocytes and platelets is regulated by hormones, most notably thrombopoietin. Megakaryocytes play a critical role in hemostasis, the process of stopping bleeding, by ensuring a continuous supply of platelets.