Classes of Angiosperms and Their Distinguishing Features

Angiosperms, or flowering plants, are divided into two main classes: monocotyledons (monocots) and dicotyledons (dicots).

Monocotyledons

Monocots are characterized by having a single cotyledon (seed leaf) in their embryo. They have parallel-veined leaves, scattered vascular bundles, and flower parts in multiples of three. The root system is typically fibrous with no main taproot. Monocots include plants such as grasses, lilies, and orchids.

Dicotyledons

Dicots are characterized by having two cotyledons in their embryo. They have net-veined leaves, a taproot system with a main root and lateral roots, and flower parts in multiples of four or five. The vascular bundles are arranged in a ring. Dicots include plants such as roses, sunflowers, and beans.

Within these two classes, there are also several subclasses and orders based on further distinguishing features:

Subclass: Magnoliidae

Flowers have multiple whorls of petals and sepals, often large and showy

Vascular tissue arranged in a ring

Examples include magnolias, laurels, and water lilies

Subclass: Hamamelidae

Flowers have four or five petals

Vascular tissue arranged in a ring

Examples include witch hazels, birches, and planes

Subclass: Caryophyllidae

Flowers have five petals

Vascular tissue arranged in a ring

Examples include carnations, beets, and spinach

Subclass: Dilleniidae

Flowers have four or five petals and sepals

Vascular tissue arranged in a ring or scattered

Examples include roses, violets, and beans

Subclass: Asteridae

Flowers have five fused petals and sepals

Vascular tissue arranged in a ring or scattered

Examples include daisies, sunflowers, and mint

Subclass: Liliidae

Flowers have six petals and sepals, often fused

Vascular tissue arranged in a ring or scattered

Examples include lilies, irises, and onions

The distinguishing features of these classes and subclasses are based on the number and arrangement of flower parts, leaf venation, and the organization of vascular tissue in the stem. These features help botanists identify and classify different species of flowering plants.