( ( Photosynthetic organisms ) ( ( ( ( ( obtain ( their energy ) ) ( from ( the sun ) ) ) and ) ( use ( this ( energy ( to ( make food ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Photosynthetic) (NNS organisms)) (VP (VP (VB obtain) (NP (PRP$ their) (NN energy)) (PP (IN from) (NP (DT the) (NN sun)))) (CC and) (VP (VB use) (NP (DT this) (NN energy) (S (VP (TO to) (VP (VB make) (NP (NN food)))))))) (. .)))
Photosynthetic organisms     obtain their energy from the sun and use this energy to make food.
(ROOT (S (NP (NP (DT The) (NN energy)) (VP (VBN stored) (PP (IN in) (NP (NP (DT the) (JJ organic) (NNS molecules)) (PP (IN of) (NP (NN food))))))) (ADVP (RB ultimately)) (VP (VBZ comes) (PP (IN from) (NP (DT the) (NN sun)))) (. .)))
The energy stored in the organic molecules of food ultimately comes from the sun.