( ( The chromosome ) ( ( is ( ( ( ( made up ) ( of two ) ) ( ( ( very long ) ( single strands ) ) ( of ( ( a chemical ) ( called ( ( DNA ( -LRB- ( ( deoxyribonucleic acid ) -RRB- ) ) ) ( that ( are ( wrapped ( around ( each other ) ) ) ) ) ) ) ) ) ) ) ( to ( form ( a ( double helix ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN chromosome)) (VP (VBZ is) (VP (VBN made) (PRT (RP up)) (PP (IN of) (NP (CD two))) (NP (NP (ADJP (RB very) (JJ long)) (JJ single) (NNS strands)) (PP (IN of) (NP (NP (DT a) (NN chemical)) (VP (VBN called) (NP (NP (NNP DNA)) (PRN (-LRB- -LRB-) (NP (JJ deoxyribonucleic) (NN acid)) (-RRB- -RRB-)) (SBAR (WHNP (WDT that)) (S (VP (VBP are) (VP (VBN wrapped) (PP (IN around) (NP (DT each) (JJ other)))))))))))) (S (VP (TO to) (VP (VB form) (NP (DT a) (JJ double) (NN helix))))))) (. .)))
The chromosome is made up of two very long single strands of a chemical called DNA (deoxyribonucleic acid) that are wrapped around each other to form a double helix.
(ROOT (S (NP (DT The) (JJ double) (NN helix) (NN dna) (NN shape)) (VP (VBZ forms) (SBAR (WHADVP (WRB when)) (S (NP (DT the) (CD two) (JJ nucleotide) (NNS chains)) (VP (VB wrap) (PRT (RP around)) (NP (DT the) (JJ same) (NNS axis)))))) (. .)))