( ( Platelets ( ( ( A component ) ( of blood ) ) ( that ( ( ( ( ( ( stick ( together ( to ( form ( a plug ) ) ) ) ) , ) or ) clot ) , ) ( when ( ( ( certain substances ) ( beneath ( the ( blood ( vessel lining ) ) ) ) ) ( are ( exposed ( to ( circulating blood ) ) ) ) ) ) ) ) ) ) . )
(ROOT (S (VP (VB Platelets) (NP (NP (DT A) (NN component)) (PP (IN of) (NP (NN blood))) (SBAR (WHNP (WDT that)) (S (VP (VBP stick) (S (ADVP (RB together)) (VP (TO to) (VP (VB form) (NP (DT a) (NN plug))))) (, ,) (CC or) (VBP clot) (, ,) (SBAR (WHADVP (WRB when)) (S (NP (NP (JJ certain) (NNS substances)) (PP (IN beneath) (NP (DT the) (NN blood) (NN vessel) (NN lining)))) (VP (VBP are) (ADJP (VBN exposed) (PP (TO to) (S (VP (VBG circulating) (NP (NN blood)))))))))))))) (. .)))
Platelets A component of blood that stick together to form a plug, or clot, when certain substances beneath the blood vessel lining are exposed to circulating blood.
(ROOT (S (NP (NNS Platelets)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (NP (DT the) (NN cell) (NNS fragments)) (VP (VBN involved) (PP (IN in) (NP (NP (NN blood) (NN clotting)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBP stick) (PP (PP (TO to) (NP (NP (NNS tears)) (PP (IN in) (NP (NN blood) (NNS vessels))))) (CC and) (PP (TO to) (NP (DT each) (JJ other)))))))))))))) (. .)))