( ( ( Each ribosome ) ( is ( ( a complex ) ( of ( ( proteins and ) ( special RNA ) ) ) ) ) ) ( ( called ( ( ribosomal RNA ) ( -LRB- ( rRNA -RRB- ) ) ) ) . ) )
(ROOT (SINV (S (NP (DT Each) (NN ribosome)) (VP (VBZ is) (NP (NP (DT a) (NN complex)) (PP (IN of) (NP (NP (NNS proteins)) (CC and) (NP (JJ special) (NNS RNA))))))) (VP (VBD called)) (NP (NP (NNP ribosomal) (NNP RNA)) (PRN (-LRB- -LRB-) (NP (NNP rRNA)) (-RRB- -RRB-))) (. .)))
Each ribosome is a complex of proteins and special RNA called ribosomal RNA (rRNA) .
(ROOT (S (NP (DT A) (NN ribosome)) (VP (VBZ consists) (PP (IN of) (NP (NP (CD two) (NNS elements)) (, ,) (NP (NN rrna)) (CC and) (NP (NNS proteins))))) (. .)))
A ribosome consists of two elements, rrna and proteins.