( ( ( Germ ( Cells ( and ( Fertilization ( Meiosis ( Sperm ( Eggs Fertilization ) ) ) ) ) ) ) 21 ) . )
(ROOT (NP (NP (NNP Germ) (NNPS Cells) (CC and) (NNP Fertilization) (NNP Meiosis) (NNP Sperm) (NNP Eggs) (NNP Fertilization)) (NP (CD 21)) (. .)))
Germ Cells and Fertilization Meiosis Sperm Eggs Fertilization 21.
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (DT a) (NN sperm)) (VP (VBZ penetrates) (NP (DT the) (NN egg))))) (, ,) (NP (PRP it)) (VP (VBZ triggers) (NP (DT the) (NN egg) (S (VP (TO to) (VP (VB complete) (NP (NNS meiosis))))))) (. .)))