( ( control ( of ( their diameter ) ) ) ( ( is ( depending ( on ( changes ( in ( precapillary ( and ( post ( capillary resistance ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NN control)) (PP (IN of) (NP (PRP$ their) (NN diameter)))) (VP (VBZ is) (VP (VBG depending) (PP (IN on) (NP (NP (NNS changes)) (PP (IN in) (NP (NN precapillary) (CC and) (NN post) (NN capillary) (NN resistance))))))) (. .)))
control of their diameter is depending on changes in precapillary and post capillary resistance.
(ROOT (NP (NP (NP (DT The) (ADJP (RB precapillary) (JJ sphincters)) (NN regulate)) (PRN (-LRB- -LRB-) (PRP s) (-RRB- -RRB-))) (NP (NP (DT the) (NN passage)) (PP (IN of) (NP (NP (NN blood)) (PP (IN into) (NP (JJ capillary) (NNS beds)))))) (. .)))