( ( Active ( mediated transport ) ) ( ( ( ( ( ( involves transport ) ( against ( a ( concentration gradient ) ) ) ) , ) and ) ( requires energy ) ) . ) )
(ROOT (S (NP (JJ Active) (JJ mediated) (NN transport)) (VP (VP (VBZ involves) (NP (NN transport)) (PP (IN against) (NP (DT a) (NN concentration) (NN gradient)))) (, ,) (CC and) (VP (VBZ requires) (NP (NN energy)))) (. .)))
Active mediated transport involves transport against a concentration gradient, and requires energy.
(ROOT (S (NP (NNP Passive) (NN transport)) (VP (VP (VBZ requires) (NP (DT no) (NN energy))) (CC and) (VP (VBZ occurs) (SBAR (WHADVP (WRB when)) (S (NP (NNS substances)) (VP (VBP move) (PP (IN from) (NP (NP (NNS areas)) (PP (IN of) (NP (NP (JJR higher)) (PP (TO to) (NP (JJR lower) (NN concentration)))))))))))) (. .)))