The seeds of some plants will not normally germinate until they have been in the ground for several months. Some seeds were collected from a plant of this type. The seeds were divided into three groups. Each group of seeds was put into a shallow dish and covered with water. The lid that was used was loose fitting so that oxygen could reach the seeds. Group 1 were intact seeds. Group 2 were seeds from which the testas had been removed. Group 3 were seeds from which the testas had been removed, but the testas were placed separately in the same dish. [Figure 33.1] Only the seeds in Group 2 germinated. What would be the most logical extension of this experiment?

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