Difference Between Monocotyledon and Dicotyledon

What is Monocotyledon?

Monocotyledons (Liliopsida) are a class of flowering plants, including more than 75 000 species. They are mostly herbaceous. The name of the class comes from the structure of the seeds, which have one cotyledon, with a terminal position.

The seeds of Monocotyledons have a well-developed endosperm. It usually stores starch and proteins, necessary for the initial growth of the plant. The seed germination of the Monocotyledons is usually hypogeal.

The leaves of Monocotyledons are simple, with isobilateral symmetry. They have parallel veins, smooth edge, and long sheath, always covering the stem. The stomata are distributed equally on both surfaces of the leaves.

The main root is not developed, so the root system is adventitous.

The flowers are with a simple calix. The number of individual parts of the flowers is equal to or multiple to three.

The stem can be hollow or solid. Vascular bundles are scattered throughout the stem. Stems and roots do not have a cambium and cannot enlarge in diameter.

The class combines about 25% of the flower plants and is divided into the following subclasses:

• Alismatidae,
• Liliidae,
• Arecidae,
• Some authors also separate also subclass – Commelinidae

Important families are Poaceae, Liliaceae (onion, garlic, tulips, and Lily of the valley), Arecaceae, Orchidaceae, Iridaceae, etc.

What is Dicotyledon?

Dicotyledons (Magnoliopsida) are a class of flowering plants, which includes more than 175 000 plant species – from annual plants to trees. The Dicotyledons are distinguished by the presence of two lateral cotyledons in each seed.

In the cotyledons are stored starch, oils, or proteins, that are used for the plant’s growth until it begins to photosynthesize. The seed germination of the Dicotyledons is hypogeal or epigeal

The leaves are simple or complex, with dorsiventral symmetry. They have net or reticulate venation and are often with uneven edges, jagged or dissected. The stomata are located on the down surface of the leaves.

The Dicotyledons have tap root system.

The number of individual parts of the flower is equal to or multiple to four or five.

The stems are solid. Vascular bundles in the stems are fewer than in the Monocotyledons and are located in rings (concentrically).

Stems and roots have a cambium and can enlarge in diameter.

Six subclasses belong to class Magnoliopsida:

• Magnoliidae,
• Hamamelidae,
• Caryophyllidae,
• Rosidae,
• Dilleniidae,
• Asteridae,
• Some researchers also separate subclasses Ranunculidae and Lamiidae.

Important families are Fabaceae, Lamiaceae, Rosaceae, Cucurbitaceae, etc.

Difference Between Monocotyledon and Dicotyledon

1.    Definitions of Monocotyledon and Dicotyledon

Monocotyledon: Monocotyledons (Liliopsida) are a class of flowering plants, distinguished by the presence of one terminal cotyledon in each seed. They are mostly herbaceous.

Dicotyledon: Dicotyledons (Magnoliopsida) are a class of flowering plants, distinguished by the presence of two lateral cotyledons in each seed. They are from annual plants to trees.

2.   Cotyledons of Monocotyledon and Dicotyledon

Monocotyledon: Monocotyledons have one terminal cotyledon.

Dicotyledon: Dicotyledons have two lateral cotyledons.

3.   Seed germination of Monocotyledon and Dicotyledon

Monocotyledon: The seed germination of the Monocotyledons is usually hypogeal.

Dicotyledon: The seed germination of the Dicotyledons is epigeal or hypogeal.

4.   Leaves  of Monocotyledon and Dicotyledon

Monocotyledon: The leaves of Monocotyledons are simple, with isobilateral symmetry, with parallel veins, smooth edge, and long sheath, always covering the stem. The stomata are distributed equally on both surfaces.

Dicotyledon: The leaves are with simple or complex, with dorsiventral symmetry. They have net or reticulate venation and are often with uneven edges, jagged or dissected. The stomata are located on the down surface of the leaves.

5.   Stems of Monocotyledon and Dicotyledon

Monocotyledons: Stems do not have a cambium and cannot enlarge in diameter. They can be hollow or solid. Vascular bundles are scattered throughout the stem.

Dicotyledons: The stems  have a cambium and can enlarge in diameter. They are solid. Vascular bundles in the stems are fewer than in the Monocotyledons and are located in rings (concentrically).

6.   Root and Root System  of Monocotyledon and Dicotyledon

Monocotyledons: The main root in Monocotyledons is not developed, so the root system is adventitous. The roots do not have a cambium and cannot enlarge in diameter.

Dicotyledons: The Dicotyledons have tap root system. The roots have a cambium and can enlarge in diameter.

7.   Flowers of Monocotyledon and Dicotyledon

Monocotyledons: The number of individual parts of the flowers is equal to or multiple to three.

Dicotyledons: The number of individual parts of the flower is equal to or multiple to four or five.

Summary:

• Monocotyledons (Liliopsida) are a class of flowering plants, distinguished by the presence of one terminal cotyledon in each seed. They are mostly herbaceous.
• Dicotyledons (Magnoliopsida) are a class of flowering plants, distinguished by the presence of two lateral cotyledons in each seed. They are from annual plants to trees.
• In the cotyledons are stored substances, that are used for the plant’s growth until it begins to photosynthesize.
• The seed germination is usually hypogeal for the Monocotyledons and epigeal or hypogeal for the Dicotyledons.
• The leaves of Monocotyledons are simple, with isobilateral symmetry, with parallel veins, smooth edge, and long sheath, always covering the stem. The leaves of Dicotyledons are with simple or complex, with dorsiventral symmetry. They have net or reticulate venation and are often with uneven edges, jagged or dissected.
• In Monocotyledons the stomata are distributed equally on both surfaces, while in Dicotyledons they are located only on the down surface of the leaves.
• The roots and stems of Monocotyledons do not have a cambium and cannot enlarge in diameter, while in Dicotyledons they have a cambium and can enlarge in diameter.
• The Monocotyledons have hollow stems with vascular bundles scattered throughout the stem. The Dicotyledons have solid stems with vascular bundles located in rings (concentrically).
• The Monocotyledons have adventitous root system is, while the Dicotyledons have tap root system. adventitious
• The number of individual parts of the flowers of Monocotyledons is equal to or multiple to three, and of Dicotyledons – equal to or multiple to four or five.