03 primary hemostasis

a series of complex processes by which the body spontaneously stops bleeding and maintains blood on its fluid state within the blood vessel

• homeostasis

• vascular response

• hemostasis

• clotting

life span of platelets

• 3 - 5 days

• 1 - 3 days

• 2 - 3 weeks

• 7 - 10 days

normal value of platelets

• 100 - 200 x 10^9/L

• 150 - 400 x 10^8/L

• 100 - 200 x 10^8/L

• 150 - 400 x 10^9/L

megakaryopoiesis takes about how many days?

• 2 - 3 days

• 5 - 7 days

• 1 - 2 weeks

• 10 - 12 days

2 growth factors involved in megakaryopoiesis

• EPO

• serotonin

• CFU-Meg

• thrombopoietin

it is the earliest recognizable stage of megakaryopoiesis

• promegakaryocyte

• megakaryoblast

• megakaryocyte

• metamegakaryocyte

stage wherein nuclear lobulation begins and cytoplasm has visible bluish stained granules

• promegakaryocyte

• megakaryoblast

• metamegakaryocyte

• megakaryocyte

stage with two or more nuclei and with a reddish blue stained granules

• megakaryoblast

• metamegakaryocyte

• megakaryocyte

• promegakaryocyte

stage with aggregated granules in the cytoplasm

• metamegakaryocyte

• promegakaryocyte

• megakaryocyte

• megakaryoblast

overall function of the platelets

• maintains vascular integrity

• release growth factors

• formation of platelet plug

• stabilize the plug by activating the fibrin or clot formation