Cotyledon facts for kids

A cotyledon (say: KOT-uh-LEE-dun) is like a special first leaf found inside a seed. When a seed starts to grow, a process called sprouting, the cotyledons are the very first leaves that appear on the young plant.

Cotyledons often look quite different from the plant's later, "true" leaves. That's why they are not called true leaves. These special leaves help the young plant get the food it needs to start growing.

How Cotyledons Help Young Plants

Cotyledons help the young plant make its own food (sugars) using sunlight. This important process is called photosynthesis. The sugars created give the plant energy to grow its true leaves, stem, and roots.

After the true leaves have grown and can make enough food for the plant, the cotyledons often dry up and fall off. The plant doesn't need them anymore because its true leaves have taken over the job of making food.

One or Two: Monocots and Dicots

Plants are often grouped based on how many cotyledons they have.

• Monocots (short for monocotyledonous plants) have just one cotyledon. Examples include grasses, corn, and lilies.
• Dicots (short for dicotyledonous plants) have two cotyledons. Many common plants like beans, roses, and sunflowers are dicots.

The number of cotyledons is one of the main ways scientists classify flowering plants.

Images for kids

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  Cotyledon from a Judas-tree (Cercis siliquastrum, a dicot) seedling.

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  This picture shows a monocot (left) and a dicot (right) sprouting. The visible part of the monocot is its first true leaf; its cotyledon stays hidden inside the seed.

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  Peanut seeds split in half, showing the embryos with cotyledons and the tiny root.

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  A two-week-old Douglas fir (a type of conifer) with seven cotyledons.

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  A Mimosa pudica (a dicot) seedling with two cotyledons and its first "true" leaf.

See also

In Spanish: Cotiledón para niños