How can you tell that the corn plants were responding to gravity rather than light water or the direction the seed was pointing?

Corn plants exhibit a phenomenon called gravitropism, where their roots grow downward in response to gravity while their shoots grow upward. If the corn plants were placed in a dark environment and still demonstrated this growth direction, it would indicate a response to gravity rather than light. Additionally, if the plants were rotated, but their roots continued to grow downward and shoots upward, this further supports the conclusion that gravity is the primary factor influencing their growth orientation. Other factors like water and seed orientation would not consistently produce the same directional responses.