Childrens Illustrated Encyclopedia

(Marvins-Underground-K-12) #1

227


Fruits and seeds

Roots lengthen.

In the fall, the badger picks up many seeds on its
fur as it pushes through undergrowth. The seeds
eventually drop off and grow into new plants.

Wind
The light, winged, helicopter-
shaped fruits of sycamore trees
twirl in the wind, far away from
the parent tree. Pines also have
winged seeds. Many plants, such
as cotton and dandelions, have
seeds with fine silky plumes or
parachutes that catch
the breeze.

Find out more
Birds
Flowers and herbs
Plants
Trees

GerMinaTion
Seeds need warmth,
moisture, and air in
order to germinate
(grow). The seeds of
certain tropical plants
start to germinate within
a few days; the seeds of
most other plants remain
dormant, or asleep, until
conditions are right.
Many tree and shrub
seeds must pass through
a cold winter before they
can begin to grow.

First true
leaves
open.

Shoot
lengthens.

Plumule
grows
upward.

Roots
develop
branches.

Seed is
contained
inside fruit.

Sycamore fruit
has wings to
carry it through
the air.

BurierS
Squirrels
bury nuts to eat during the winter.
Sometimes squirrels forget where
they have buried these
nuts, and the forgotten
seeds may sprout the
following spring.

Radicle
(young
root)

WheaT
The seeds of
cereals such as
wheat and
other grasses
have only one
seed leaf. These
seeds are called
monocotyledons.

First
leaves

Young
shoot

Root hairs
begin to
grow.

runner Bean
a runner bean has a food store
in the form of two seed leaves
that are called cotyledons.

First true
leaves

Plumule
(young shoot)

hoW SeedS are SPread
Plants have several ways of spreading their seeds.
Some seeds have wings or parachutes that are blown
by the wind. The coconut plant has seeds that float and are
carried on water. The sweet pea has a pod that snaps open
and flings the seeds out. animals also disperse seeds. Birds
eat berries and other fruits, then drop the seeds as they
feed or pass them out
after digestion.

Radicle
(young root)
begins to
grow.

BirdS
Birds and
monkeys
are the main
seed spreaders
for many fruits.
Seeds stick to the bird’s bill
to be wiped off later on a
branch or the ground.

acorn
a large oak tree
bears thousands of ripe
fruits called acorns. animals
cannot eat them all; a few
survive to grow into new oak trees.
WaTer
aquatic plants such as water lilies
and lotus flowers produce fruits
that float away downriver
on water currents. The
fruits often grow
into new plants
far away from
the parent
plant.

The lotus flower
lives in water. Its
seeds float away
downstream to
grow elsewhere.
hookS and BurrS
numerous kinds of fruits and seeds have hooks and
burrs on their outer casings. These hooks catch onto
the fur or feathers of a passing mammal or bird and
sometimes on to our shoes, socks, and clothing, to fall
off later. Well-known
hooked fruits are
burdock, cleavers,
agrimony, and South
african grapple fruit.

exPloSive
PodS
Fruits such as those of
the lupin are still soft
and fleshy when they shed
their seeds. When they are
fully ripe, the casing suddenly
splits open, and the seeds pop out
with explosive force.

dandelion
each time you
blow on the head
of a dandelion
you spread the
seeds on their
feathery parachutes.

Dormant
seed

Testa (seed
case)
containing
seed leaves

US_227_Fruits_Seeds_2.indd 227 21/01/16 4:59 pm

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