blood 2 Flashcards
(32 cards)
whats the second most abundant white blood cells
lymphocytes
do plates have nucleus
no
what are considered to be not true cells
platelets
what is a mogakaryote
organism that produces platelets
whats the lifespan of platelets
about 10 days
what are the two types of granules in platelets
dense core granules
a-granules
what cell is very important in hemostasis
platelets
what is hemostasis
the prevention of blood loss from a damaged vessel
whats the three step process to hemostasis
vasoconstriction
platelets plug formation
clot (coagulation cascade)
how do platelets attach to the vessel wall
their cell surface receptors
what are platelet cell surface receptors activated by
collagen and laminin that get exposed when a cut happens
when does the release of platelet factors happen
after they’ve bonded to their receptors
what is platelet formation an example of
positive feedback loop
what do intact endothelial cells do
they release substances to prevent activated platelets from binding
what causes platelets to form molecular bridges between one another
von willebrand factor
what stabilizes the the platelet plug into a clot
a fibrin protein mesh
what initiates the intrinsic pathway
factor XII (12)
what ends the intrinsic pathway
activated factor X (10)
what starts the extrinsic pathway
factor VII (7)
what ends the intrinsic pathway
active factor X (10)
what happens to b both active factor 10 created
they converge into the same pathway known as the common pathway
what does the common pathway produce
prothrombinase
what does prothrombinase convert
prothrombin to thrombin
what is thrombin
a central protease of the coagulation cascade