Thrombocytes Flashcards
basics of thrombocytes.
- they are not cells, but fragments of megakaryocytes.
2. normal thrombocytes counts is 90k-270k Μl or μL.
what is normal thrombocyte count?
90k-270k Μl or μL
thrombocytopoiesis
production of thrombocytes from megakaryocytes in the bone marrow.
simplified thrombocytopoiesis.
- pluripotent stem cells.
- committed stem cells
- CFU-mega
- Megakaryoblast
- basophil megakaryocyte
- Granular megakaryocyte
- mature megakaryocyte
- thrombocytes
hormone responsible for thrombocytopoiesis
thrombopoietin
role of thrombopoietin.
- regulate thrombocytes production, increase number and rate of mature of megakaryocytes.
thrombocytopenia
is a disorder in which the body produces few thrombocytes.
thrombocytosis
is the disorder in which the body produce too many thrombocytes.
main parts of thrombocytes.
- surface connecting tubules
- dense tubules
- mitochondria
- glycogen
- dense granules
- alpha granules
- microtubules
- coat
main roles of thrombocytes.
- role in the immunity
- role in clot formation and retraction.
- role in transport and storage function.
- role in the repair of injured blood vessels
- role in hemostasis: vasoconstriction and platelet plug formation in vessel repair.
how thrombocytes involve in the storage and transport function?
Thrombocytes store and transport chemicals used in the clot formation processes. Eg: histamine etc.
how thrombocytes are involved in immunity?
Platelets sense invading pathogens through their receptors, which results in platelet activation. Activated platelets release antimicrobial proteins and molecules that regulate the host’s response to infection.
how do thrombocyte vasoconstricts local vessels?
Platelets release cytoplasmic granules which contain serotonin and other chemicals which increase the effect of vasoconstriction.
what is clot retraction?
Clot retraction is the “shrinking” of a blood clot over a number of days.
what is vascular spasm
is a sudden, brief tightening of the muscle cells inside the walls of a blood vessel.