What is the structure known as a bulb primarily classified as?

A bulb is primarily classified as a type of underground storage organ, specifically referred to as a bulbus in botanical terminology. Bulbs consist of a short stem surrounded by fleshy leaves or leaf bases, which store nutrients and energy for the plant. This structure enables the plant to survive adverse conditions, such as drought or cold temperatures, and allows it to regenerate in the next growing season.

Understanding the characteristics of bulbs is important in distinguishing them from other underground structures. For instance, rhizomes are horizontal, underground stems that produce new shoots and roots, while tubers are swollen storage organs that typically develop from the tips of stolons or rhizomes. Roots, on the other hand, primarily serve anchorage and nutrient absorption rather than storage. The classification of bulbs as bulbus highlights their specific function and structure in the plant kingdom.