( ( ( The ( first parts ) ) ( of ( the ( general ( defence system ) ) ) ) ) ( ( ( are really ) ( barriers ( that ( ( stop ( the pathogens ) ) ( from ( entering ( the body ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ first) (NNS parts)) (PP (IN of) (NP (DT the) (JJ general) (NN defence) (NN system)))) (VP (VBP are) (ADVP (RB really)) (NP (NP (NNS barriers)) (SBAR (WHNP (WDT that)) (S (VP (VBP stop) (NP (DT the) (NNS pathogens)) (PP (IN from) (S (VP (VBG entering) (NP (DT the) (NN body)))))))))) (. .)))
The first parts of the general defence system are really barriers that stop the pathogens from entering the body.
(ROOT (S (NP (DT The) (JJ innate) (JJ immune) (NN system)) (VP (VBZ serves) (PP (IN as) (NP (NP (DT a) (JJ first) (NN responder)) (PP (TO to) (NP (NP (JJ pathogenic) (NNS threats)) (SBAR (WHNP (WDT that)) (S (VP (VB bypass) (NP (NP (JJ natural) (ADJP (NN physical) (CC and) (NN chemical)) (NNS barriers)) (PP (IN of) (NP (DT the) (NN body)))))))))))) (. .)))