Based on the student's investigation, the effect of root space on plant growth can be observed through the average heights of the plants in Group A and Group B over the six weeks. Group A’s plants, which were grown in 3 cm deep containers, showed an average height increase from 2 cm in week 1 to 10 cm in week 6. In contrast, Group B’s plants, grown in 10 cm deep containers, started at 3 cm in week 1 and grew to 18 cm by week 6.
The data clearly shows that plants in Group B, which had a deeper root space, consistently grew taller than those in Group A. By week 6, Group A plants reached an average height of 10 cm while Group B plants reached an average height of 18 cm. This indicates that the deeper root space allowed plants in Group B to access a greater volume of soil, providing more nutrients and space for roots to expand, which positively influenced their growth.
To determine whether the observed effect was due to environmental or genetic factors, we could still ensure that both groups of plants are of the same genetic variety. The controlled conditions (same amount of water, sunlight, and soil type) for both groups help isolate the root space (the independent variable) as the main influencing factor. If the plants in both groups were genetically identical and the environment was identical (except for the root space), we could reasonably conclude that the differences in growth were likely due to root space rather than genetic variation or environmental disparities. Therefore, the data supports the conclusion that increased root space enhances plants’ growth due to improved access to resources.