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A
seed is a living organism. To be more exact,
a seed contains a living organism. The
tiny structure inside a seed is the embryo.
An embryo is a living baby plant. The embryo
is in a dormant, or inactive, stage. The embryo is
waiting for the right conditions to start growing.
But there is more to a seed. The largest
part of the seed is food storage. The storage
structures are called
cotyledons
. Some seeds,
such as beans, peas, and sunflowers, have two
cotyledons. Seeds of grasses, such as corn, rice,
and wheat, have one cotyledon.
The embryo and cotyledons are wrapped in
a tough outer layer called the seed coat. Some
seed coats are thin, like the coat on bean and
pea seeds. Other seed coats are tough and woody,
like the shell on a peanut or sunflower seed.
And there are seeds with coats so hard you
need a tool to open them. Coconuts, walnuts,
almonds, and other nuts have very hard seed
coats. The seed coat protects the embryo.
Cotyledon
Seed coat
Embryo
A bowl of
mixed nuts
Sunflower
seeds
A coconut
Germination
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