Platelets and Thrombopoiesis

These flashcards cover key concepts related to platelets, their function, structure, and the processes of thrombopoiesis and hemostasis.

Platelets

Small, disc-shaped cell fragments in blood that prevent bleeding by participating in blood clotting.

Thrombopoiesis

The process by which platelets are produced in the bone marrow from megakaryocytes.

Primary Hemostasis

The initial phase of blood coagulation where a platelet plug is formed at the site of vascular injury.

Thrombocytopenia

A condition characterized by an abnormally low platelet count in the blood.

Thrombocytosis

A condition where there is an abnormally high platelet count in the blood.

Granules

Cellular components in platelets that contain substances crucial for hemostasis and coagulation.

C MPL

Receptor for thrombopoietin that activates pathways for platelet production and megakaryocyte differentiation.

Mean Platelet Volume (MPV)

A measure of the average size of platelets in the blood.

Megakaryocyte

A large bone marrow cell that produces platelets.

Reactive Thrombocytosis

An increase in platelet count due to conditions such as infection or inflammation.

Endomitosis

A process where the nucleus of a cell divides but the cell does not divide, occurring in megakaryocytes.

Vascular Injury

Damage to blood vessels that triggers platelet activation and blood clot formation.

Fibrin

A protein that stabilizes the platelet plug during secondary hemostasis.

Phospholipid Bilayer

A double layer of phospholipids that makes up the cell membrane of platelets.

Microtubules

Cytoskeletal structures within platelets that maintain their shape and support aggregation.

Hemostasis

The process that prevents and stops bleeding, involving vascular constriction, platelet activation, and coagulation.