( ( ( ( phospholipids ( ( ( are ( ( an ( essential component ) ) ( in ( all ( cell membranes ) ) ) ) ) , ) ( where ( ( ( ( ( ( ( their ( form flexible ) ) , ) ( self healing ) ) , ) semipermiable ) , ) ( ( double ( layered boundaries ) ) ( between ( the cell ) ) ) ) ) ) ) and ) ( it ( surrounding environment ) ) ) . )
(ROOT (S (S (NP (NNS phospholipids)) (VP (VBP are) (NP (NP (DT an) (JJ essential) (NN component)) (PP (IN in) (NP (DT all) (NN cell) (NNS membranes)))) (, ,) (SBAR (WHADVP (WRB where)) (FRAG (NP (NP (PRP$ their) (NN form) (JJ flexible)) (, ,) (NP (NN self) (NN healing)) (, ,) (NP (NN semipermiable)) (, ,) (NP (NP (JJ double) (JJ layered) (NNS boundaries)) (PP (IN between) (NP (DT the) (NN cell))))))))) (CC and) (S (NP (PRP it)) (VP (VBG surrounding) (NP (NN environment)))) (. .)))
phospholipids are an essential component in all cell membranes, where their form flexible, self healing, semipermiable, double layered boundaries between the cell and it surrounding environment.
(ROOT (S (NP (DT The) (NN cell) (NN membrane)) (VP (VBZ consists) (PP (IN of) (NP (NP (CD two) (JJ adjacent) (NNS layers)) (PP (IN of) (NP (NNS phospholipids)))))) (. .)))