Final answer:
The disappearance of the pericycle in a plant's root would lead to the loss of the plant’s ability to produce lateral roots, affecting the growth and stability.
Step-by-step explanation:
If the pericycle disappeared in a plant's root structure, the most likely result would be that the root would lose the ability to produce lateral roots. This happens because the pericycle is a ring of parenchyma cells located just inside the endodermis, and these cells can differentiate into apical meristems that give rise to lateral roots.
Without the pericycle layer, this crucial process of generating new roots would be impaired, potentially affecting the plant's overall growth and stability. This would not directly affect water and nutrient absorption or the root growth rate, those functions are primarily facilitated by other structures such as root hairs and the vascular tissue.
Hydrophytes are plants that live in water, and they do not need to support their own weight or transport water and nutrients over long distances. The pericycle is responsible for both of these functions, so it is not needed by hydrophytes.
In addition, the pericycle is a site of lateral root development. Hydrophytes do not need to develop lateral roots as extensively as terrestrial plants because they have access to water and nutrients from all sides.