( ( In ( ( the ( ( epipelagic ( , ( or uppermost ) ) ) zone ) ) ( of ( the ( open ocean ) ) ) ) ) ( , ( ( ( ( phytoplankton ( -LRB- ( ( plant plankton ) -RRB- ) ) ) and ) ( zooplankton ( -LRB- ( ( animal plankton ) -RRB- ) ) ) ) ( ( ( ( are concentrated ) , ) ( forming ( ( the base ) ( of ( the ( marine ( food chain ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NP (DT the) (ADJP (JJ epipelagic) (, ,) (CC or) (JJ uppermost)) (NN zone)) (PP (IN of) (NP (DT the) (JJ open) (NN ocean))))) (, ,) (NP (NP (NP (NN phytoplankton)) (PRN (-LRB- -LRB-) (NP (NN plant) (NN plankton)) (-RRB- -RRB-))) (CC and) (NP (NP (NN zooplankton)) (PRN (-LRB- -LRB-) (NP (NN animal) (NN plankton)) (-RRB- -RRB-)))) (VP (VBP are) (ADJP (JJ concentrated)) (, ,) (S (VP (VBG forming) (NP (NP (DT the) (NN base)) (PP (IN of) (NP (DT the) (JJ marine) (NN food) (NN chain))))))) (. .)))
In the epipelagic, or uppermost zone of the open ocean, phytoplankton (plant plankton) and zooplankton (animal plankton) are concentrated, forming the base of the marine food chain.
(ROOT (S (NP (NNP Phytoplankton)) (VP (VBP make) (NP (NP (NN food)) (PP (IN via) (NP (NN photosynthesis))))) (. .)))