A student had heard in his biology class that placing a ripe apple into a closed container with an unripe fruit would cause the unripe fruit to ripen. The student set up an experiment in which an unripe banana was placed into a paper bag. A second unripe banana was placed into a separate bag with an ripened apple and sealed shut. Both bags were allowed to sit undisturbed at room temperature for 48 hours. The student noted that after 48 hours, the first banana was still green and unripe. The second banana was yellow and soft to the touch.
Which statement best represents a conclusion the student might reach?