Stipule – Definition & Detailed Explanation – Botanical Terms Glossary

What is a stipule?

A stipule is a small, leaf-like structure that is found at the base of a leaf stalk, known as the petiole, in many plants. Stipules are typically paired and can vary in size, shape, and texture depending on the plant species. They are considered to be modified leaves and can be found in a wide range of plant families.

What are the functions of stipules?

Stipules serve a variety of functions in plants. One of the primary functions of stipules is to protect the young, developing leaves as they emerge from the bud. Stipules can also help regulate the amount of light that reaches the leaf surface, as well as provide support and stability to the leaf structure. In some plants, stipules may also play a role in water and nutrient absorption.

What are the different types of stipules?

There are several different types of stipules that can be found in plants. Some plants have stipules that are small and inconspicuous, while others have large, showy stipules that are highly ornamental. Stipules can be classified into several categories based on their shape, size, and attachment to the petiole. Some common types of stipules include foliaceous stipules, spiny stipules, and glandular stipules.

How do stipules vary in shape and size?

Stipules can vary greatly in shape and size depending on the plant species. Some stipules are narrow and elongated, while others are broad and rounded. Stipules can also be lobed, toothed, or have intricate patterns. In terms of size, stipules can range from being almost microscopic to several centimeters in length. The variation in shape and size of stipules is often used as a key characteristic in plant identification.

What is the significance of stipules in plant identification?

Stipules play a crucial role in plant identification, as they can provide important clues about the plant species. The presence or absence of stipules, as well as their size, shape, and texture, can help botanists differentiate between different plant families, genera, and species. Stipules are often used in conjunction with other plant characteristics, such as leaf shape, flower structure, and growth habit, to accurately identify plants in the field.

How do stipules differ from other plant structures like leaves or petioles?

Stipules are often confused with other plant structures, such as leaves or petioles, but they have distinct differences. Stipules are typically smaller and more delicate than leaves, and they are usually found at the base of the petiole, rather than along the stem. Stipules are also considered to be modified leaves, whereas petioles are leaf stalks that connect the leaf blade to the stem. Understanding the differences between stipules and other plant structures is essential for accurate plant identification and classification.