Page 155 - Ultimate Visual Dictionary (DK)

GERMINATION
EPIGEAL GERMINATION Epicotyl Epicotyl
Black bean (upper part Hypocotyl (upper part
(Phaseolus sp.) of axis) (region between of axis)
epicotyl and
Plumule radicle) Testa
(embryonic (seed coat)
shoot)
Radicle Plumule
(embryonic (embryonic
Testa root) shoot)
(seed coat)
Hilum
(point of
Raphe attachment
(ridge) to ovary)
Testa
(seed coat) Cotyledon
(seed leaf) Cotyledon
Hilum (point (seed leaf)
of attachment
to ovary) LONGITUDINAL SECTION Hypocotyl
THROUGH SEED AT START OF (region between
Micropyle GERMINATION epicotyl and radicle)
(pore for
water
absorption) First foliage Lateral root
leaf fully
grown
Petiole Growing
(leaf stalk) point

Cotyledon (seed
leaf) withers

EXTERNAL VIEW OF SEED AT
START OF GERMINATION
Primary root
First foliage leaf Cotyledon (elongated
protected by cotyledons (seed leaf) radicle)
(seed leaves)

Hypocotyl
“hook” pushes
out of soil Hypocotyl (region
Testa between epicotyl
(seed and radicle)
coal) Hypocotyl (region straightens RADICLE BREAKS THROUGH
splits between epicotyl and and lengthens TESTA AND LENGTHENS
radicle) elongates
Testa (seed Testa (seed
coal) shed coat) begins to
disintegrate
Lateral
root
Root
Root

Primary
root
HYPOCOTYL
STRAIGHTENS, Root cap
HYPOCOTYL PULLING LEAVES FIRST FOLIAGE (protective
“HOOK” APPEARS AND COTYLEDONS LEAVES FULLY covering for
ABOVE SOIL OUT OF SOIL DEVELOPED root tip)
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