( Diffusion ( ( is ( ( the process ) ( when ( particles ( ( move ( from ( areas ( of ( high concentration ) ) ) ) ) ( to ( areas ( of ( low concentration ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Diffusion)) (VP (VBZ is) (NP (NP (DT the) (NN process)) (SBAR (WHADVP (WRB when)) (S (NP (NNS particles)) (VP (VBP move) (PP (IN from) (NP (NP (NNS areas)) (PP (IN of) (NP (JJ high) (NN concentration))))) (PP (TO to) (NP (NP (NNS areas)) (PP (IN of) (NP (JJ low) (NN concentration)))))))))) (. .)))
Diffusion is the process when particles move from areas of high concentration to areas of low concentration.
(ROOT (S (NP (NNP Diffusion)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (NP (DT the) (NN movement)) (PP (IN of) (NP (NP (NNS molecules)) (PP (IN from) (NP (NP (DT an) (NN area)) (PP (IN of) (NP (NP (JJ high) (NN concentration)) (PP (TO to) (NP (NP (DT an) (NN area)) (PP (IN of) (NP (JJ low) (NN concentration))))))))))))))) (. .)))