What is a legume?

A legume refers to a family of plants where the seeds are produced in fruits known as pods. This classification includes a variety of plants, such as peas, beans, lentils, and peanuts. The defining characteristic of legumes is their ability to fix nitrogen from the atmosphere, thanks to a symbiotic relationship with certain bacteria in their root nodules. This process enriches the soil with nitrogen, making legumes particularly valuable in crop rotation and sustainable agriculture.

The other definitions provided do not align with the characteristics of legumes. For instance, corn is a cereal grain and does not belong to the legume family. The term for where a leaf meets the stem is called the node, which is not specific to legumes. Lastly, the description of plants that complete their life cycle over two growing years refers to biennial plants, which also do not specifically denote legumes. Thus, the correct answer accurately captures the essence of what a legume is.