Assertion: transportation | /r/Desires | the input of energy
Facets:
value: in this case
type: TEMPORAL
Source sentences:
text: If the exchange of substances occurs in the direction of the gradient, that is, in the direction of decreasing potential, there is no requirement for an input of energy from outside the system; if, however, the transport is against the gradient, it will require the input of energy, metabolic energy in this case.