( ( Intestinal microflora ) ( ( play ( ( a ( crucial role ) ) ( for ( ( ( ( ( the ( host organism ) ) ( as ( they ( ( ( produce ( various ( digestive enzymes ) ) ) and ) vitamins ) ) ) ) , ) ( as ( well as ) ) ) ( ( aiding ( the host ) ) ( in ( defence ( against ( foreign ( harmful pathogens ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Intestinal) (NNP microflora)) (VP (VBP play) (NP (NP (DT a) (JJ crucial) (NN role)) (PP (IN for) (NP (NP (NP (DT the) (NN host) (NN organism)) (SBAR (IN as) (S (NP (PRP they)) (VP (VP (VBP produce) (NP (JJ various) (NN digestive) (NNS enzymes))) (CC and) (VP (VBZ vitamins)))))) (, ,) (CONJP (RB as) (RB well) (IN as)) (S (VP (VBG aiding) (NP (DT the) (NN host)) (PP (IN in) (NP (NP (NN defence)) (PP (IN against) (NP (JJ foreign) (JJ harmful) (NNS pathogens))))))))))) (. .)))
Intestinal microflora play a  crucial role for the host organism as they produce various digestive enzymes and vitamins, as well as aiding the host in defence against foreign harmful pathogens.
(ROOT (S (NP (PRP We)) (VP (VBP call) (NP (DT the) (NN microflora)) (SBAR (IN that) (S (NP (NP (NN aid)) (PP (IN in) (NP (DT the) (NN digestion)))) (VP (VBP process) (NP (JJ intestinal) (NNS flora)))))) (. .)))
We call the microflora that aid in the digestion process intestinal flora.