What is the defining characteristic of dicotyledon plants?

The defining characteristic of dicotyledon plants is that they produce seeds with two embryonic leaves, known as cotyledons. This trait is a primary distinction between dicots and monocots, as monocots typically have only one cotyledon in their seeds. The presence of two cotyledons influences various aspects of the plant’s structure and function, including leaf arrangement, root development, and flowering patterns.

In contrast, while narrow leaves can sometimes be found in dicots, they are not universally characteristic of this group, as dicots can exhibit a wide range of leaf shapes. Similarly, not all dicots have fibrous root systems; many exhibit taproot systems instead. Finally, dicots are not limited to an aquatic habitat; they can thrive in various environments, including terrestrial ecosystems. This versatility and diversity make the two cotyledons a fundamental characteristic of dicotyledons.