- Byname:
- eudicot
eudicotyledon
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What is a eudicotyledon?
A eudicotyledon, also known as a eudicot, is any flowering plant that has two embryonic leaves, or cotyledons, in the seed. Eudicots are one of the two main groups of angiosperms, with the other being monocotyledons (monocots).
Eudicots typically have flower parts based on a plan of four or five, or multiples thereof. The leaves of eudicots are mostly net-veined, and their pollen grains have three germinal furrows or pores. Examples of eudicots include most common garden plants, shrubs and trees, and broad-leafed flowering plants, such as roses, geraniums, and hollyhocks.
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How can you tell a eudicotyledon from other types of plants?
Eudicotyledons, also known as eudicots, are angiosperms characterized by having two embryonic leaves, or cotyledons, within the seed. Most familiar flowering plants, such as trees, shrubs, and common garden plants, are eudicots.
Eudicots can be distinguished from other plants through several key features:
* Cotyledons Eudicots possess two cotyledons, while monocots have only one.
* Pollen Eudicot pollen has three furrows or pores, unlike the single pore or furrow found in monocots.
* Flower Parts Eudicots typically have flower parts in multiples of four or five, whereas monocots have flower parts in multiples of three.
* Leaf veins The leaves of eudicots are net-veined, while monocots have parallel veins.
* Vascular Bundles In eudicot stems, the vessels are arranged in a ring near the stem surface. Monocot stems have scattered vascular bundles.
* Root System Eudicots feature a taproot, while monocots have fibrous roots.4 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
What are some common examples of eudicotyledon plants?
Eudicots, also known as eudicotyledons, are a major group of flowering plants (angiosperms) that possess two embryonic leaves, or cotyledons, in the seed. Eudicots comprise approximately 175,000 known species.
Most common garden plants, shrubs, and trees, and broad-leafed flowering plants, such as roses, geraniums, and hollyhocks, are eudicots. Other familiar groups of eudicotyledon trees include birches, elms, hollies, maples, oaks, poplars, ashes, and willows.
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How do the leaves of eudicotyledons typically look?
Eudicotyledons, also known as eudicots, are angiosperms with two embryonic leaves, or cotyledons, in the seed. Eudicot leaves originate from cell divisions in the shoot apical meristem, forming a leaf primordium. Marginal meristems on the primordium's flanks initiate leaf-blade formation, leading to lobed shapes in simple leaves and leaflets in compound leaves.
Eudicot leaves display netlike venation patterns. Their anatomy reflects the habitat, with mesomorphic leaves in humid conditions, xeromorphic leaves in dry conditions, and hydromorphic leaves in aquatic environments. Mesomorphic leaves have palisade parenchyma beneath the upper epidermis and spongy parenchyma in the lower part, facilitating water uptake and gas exchange.
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How do eudicotyledon seeds differ from monocot seeds?
Eudicotyledons and monocotyledons are the two main groups of flowering plants or angiosperms. The key difference lies in the number of cotyledons, or seed leaves, within the seed. Eudicots possess two cotyledons, while monocots have only one.
In eudicots, the leaves have a network of interconnecting veins (net venation). Monocots leaves possess major veins that extend parallel to the long axis of the leaf (parallel venation).
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Why are eudicotyledons important in nature and for humans?
Eudicotyledons, also known as eudicots, are a significant group of flowering plants with approximately 175,000 known species. Most familiar garden plants, shrubs, trees, and broad-leaved flowering plants like roses and geraniums belong to this group. Eudicots are characterized by having two embryonic leaves, or cotyledons, in the seed. They are called "typical dicots" and have evolved from within another group that includes the more-basal dicots and the monocots together.
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eudicotyledon, any member of the angiosperms (flowering plants) that has a pair of embryonic leaves, or cotyledons, in the seed. There are about 175,000 known species of eudicots. Most common garden plants, shrubs and trees, and broad-leafed flowering plants, such as roses, geraniums, and hollyhocks, are eudicots. Formerly known as dicotyledons, or dicots, the eudicots are one of the two great groups of angiosperms, the other being the monocotyledons.
Taxonomic revision
One of the major changes in the understanding of the evolution of the angiosperms was the realization that the basic distinction among flowering plants is not between monocotyledon groups (monocots) and dicotyledon groups (dicots). Rather, plants thought of as being “typical dicots” have evolved from within another group that includes the more-basal dicots and the monocots together. This group of typical dicots is now known as the eudicots. Molecular-based evidence supports their being a single evolutionary lineage (monophyletic), and they are characterized by pollen that fundamentally has three furrows or pores (tricolpate), in contrast to the single pore or furrow of the monocot and basal dicot group (monosulcates).
Physical characteristics
Eudicots typically have flower parts based on a plan of four or five, or multiples thereof, although there are exceptions. Within nearly every order of the core eudicots (the largest group of eudicots), there are families with a basic “5 + 5 + (5 or 10) + (3 or 5)” floral construction. This refers to five sepals, five petals, one whorl of five stamens, often another whorl of five stamens, and finally a whorl of three or five carpels. The members of the whorls alternate with each other so that the petals are on radii midway between the sepal radii; the carpels in the center of the flower are on the same radii as the sepals but are opposite to them. When core eudicots have only five stamens, as is common, these stamens usually are the stamens of the outer whorl—that is, they alternate with the petals and are opposite the sepals. Furthermore, the carpels at least are more or less fused, and there is often a well-developed nectary disc either surrounding the base of the ovary or, less frequently, borne immediately outside the stamens. The flowers are usually perfect (e.g., with both male and female parts) and are radially symmetric.
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The leaves are net-veined in most eudicots, which means the vessels that conduct water and food show a meshlike pattern. In the stems the vessels are usually arranged in a continuous ring near the stem surface. About 50 percent of all eudicot species are woody; they show an annual increase in stem diameter as a result of the production of new tissue by the cambium, a layer of cells that remain capable of division throughout the life of these plants. Branching of stems is common, as are taproots. The microscopic pores (stomates) on the leaf surfaces are usually scattered and are in various orientations. The pollen grains have three germinal furrows or pores (tricolpate condition).