( ( ( The number ) ( of ( atoms ( allowed ( for ( a ( macromolecular structure ) ) ) ) ) ) ) ( ( is 5000 ) . ) )
(ROOT (S (NP (NP (DT The) (NN number)) (PP (IN of) (NP (NP (NNS atoms)) (VP (VBN allowed) (PP (IN for) (NP (DT a) (NN macromolecular) (NN structure))))))) (VP (VBZ is) (ADJP (JJ 5000))) (. .)))
The number of atoms allowed for a macromolecular structure is 5000.
(ROOT (S (NP (NP (DT The) (JJ low) (JJ atomic) (NN number)) (PP (IN of) (NP (NN beryllium)))) (VP (VBZ allows) (S (NP (PRP it)) (VP (TO to) (VP (VB absorb) (NP (NNPS x-rays)))))) (. .)))