( They ( ( have ( ( ( ( a ( key function ) ) ( in ( all ( body systems ) ) ) ) , ) ( including ( ( ( ( ( ( building ( the ( skeleton ( , ( teeth ( , ( skin ( , ( hair ( and ( red ( blood cells ) ) ) ) ) ) ) ) ) ) ) ) , ) ( maintaining ( body ( water homeostasis ) ) ) ) , ) and ) ( ensuring ( ( the ( proper functioning ) ) ( of ( many ( metabolic processes ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBP have) (NP (NP (DT a) (JJ key) (NN function)) (PP (IN in) (NP (DT all) (NN body) (NNS systems))) (, ,) (PP (VBG including) (S (VP (VP (VBG building) (NP (DT the) (JJ skeleton) (, ,) (NNS teeth) (, ,) (NN skin) (, ,) (NN hair) (CC and) (JJ red) (NN blood) (NNS cells))) (, ,) (VP (VBG maintaining) (NP (NN body) (NN water) (NNS homeostasis))) (, ,) (CC and) (VP (VBG ensuring) (NP (NP (DT the) (JJ proper) (NN functioning)) (PP (IN of) (NP (JJ many) (JJ metabolic) (NNS processes)))))))))) (. .)))
They have a key function in all body systems, including building the skeleton, teeth, skin, hair and red blood cells, maintaining body water homeostasis, and ensuring the proper functioning of many metabolic processes.
(ROOT (S (NP (DT The) (NN skeleton)) (VP (VP (VBZ supports) (NP (DT the) (NN body))) (, ,) (VP (VBZ protects) (NP (JJ internal) (NNS organs))) (, ,) (VP (VBZ produces) (NP (NN blood) (NNS cells))) (, ,) (CC and) (VP (VBZ maintains) (NP (NN mineral) (NNS homeostasis)))) (. .)))