( ( A vector ) ( ( is ( ( the organism ) ( that ( ( transmits ( a parasite ) ) ( from ( ( one host ) ( to another ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN vector)) (VP (VBZ is) (NP (NP (DT the) (NN organism)) (SBAR (WHNP (WDT that)) (S (VP (VBZ transmits) (NP (DT a) (NN parasite)) (PP (IN from) (NP (NP (CD one) (NN host)) (PP (TO to) (NP (DT another)))))))))) (. .)))
A vector is the organism that transmits a parasite from one host to another.
(ROOT (S (NP (NP (DT An) (NN organism)) (SBAR (WHNP (WDT that)) (S (VP (VBZ carries) (NP (NNS pathogens)) (PP (IN from) (NP (NP (CD one) (NN individual)) (PP (TO to) (NP (DT another))))))))) (VP (VBZ is) (VP (VBN called) (NP (DT a) (NN vector)))) (. .)))