( ( The mesenchyme ) ( ( consists ( of ( ( ( ( ( ( a ( proteinaceous matrix ) ) , ) ( some cells ) ) , ) and ) spicules ) ) ) . ) )
(ROOT (S (NP (DT The) (NN mesenchyme)) (VP (VBZ consists) (PP (IN of) (NP (NP (DT a) (JJ proteinaceous) (NN matrix)) (, ,) (NP (DT some) (NNS cells)) (, ,) (CC and) (NP (NNS spicules))))) (. .)))
The  mesenchyme consists of a proteinaceous matrix, some cells, and spicules.
(ROOT (S (NP (NP (DT The) (JJ sharp) (NNS projections)) (SBAR (IN that) (S (NP (JJ specialized) (NNS cells)) (VP (VBP grow))))) (VP (VBP are) (VP (VBN called) (NP (NNS spicules)))) (. .)))