(S (S (S (BASENP (NN Algae)) (VP (VP (VBP feed) (PRT (RP off))) (BASENP (DT the) (NNS nutrients)))) (CONJP (COMMA ,) (CC and)) (S (BASENP (PRP they)) (VP (VP (VBP are) (VP (CC either) (VP (VBN consumed) (PP (IN by) (BASENP (JJ aquatic) (NN life)))))) (CC or) (VP (VBP sink) (PP (IN at) (NP (BASENP (DT the) (NN end)) (PP (IN of) (BASENP (PRPD their) (NN life) (NN cycle))))))))) (PERIOD .))