ARIL (AIR-uhl)
A
fleshy cover of a seed Common
clues: Seed
cover; Seed coating; Nutmeg skin; Seed surrounder; Seed
integument; Bittersweet coating; Botanical coat; Nutmeg husk;
Seed envelope Crossword
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4 times a year News: Food
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Mature
and immature arils of Taxus
baccata,
a European yew. A fleshy aril surrounds each seed.
An
aril is a fleshy covering of certain seeds formed from the
funiculus (attachment point of the seed). The aril creates a
fruit-like structure (called a false-fruit) and is produced by a
few species of gymnosperms, notably the yews of the Family
Taxaceae. Instead of having a cone-like structure as is typical
of most gymnosperms, the reproductive structure of the yew
consists of a single seed that becomes surrounded by a fleshy,
cup-like covering. This covering is interpreted as a highly
modified scale.
In
the photograph of a European yew (Taxus baccata) above, note that
the aril starts out as a small, green band at the base of the
seed, then turns brown to red as it enlarges and surrounds the
seed, eventually becoming fleshy and scarlet in color at
maturity. The aril is attractive to birds and non-toxic (all
other parts of the yew are toxic), serving therefore to promote
dispersal of the yew seed by birds.
The
term aril is not limited to yews. It means any specialized
outgrowth from the funiculus (or hilum) that covers or is
attached to the seed. It is sometimes applied to any appendage or
thickening of the seed coat in flowering plants, an example being
the edible parts of the pomegranate fruit.
This
article is licensed under the GNU
Free Documentation License.
It uses material from the Wikipedia
article "Aril".
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