dài xiè
replacement
substitution
metabolism (biol.)
xīn chén dài xiè
metabolism (biology)
the new replaces the old (idiom)
fēn jiě dài xiè
catabolism (biology)
metabolic breaking down and waste disposal
dissimilation
hé chéng dài xiè
anabolism (biology)
constructive metabolism (using energy to make proteins etc)
assimilation