Download Plants Roots and Stems

Plants
Roots and Stems
Roots
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Roots:
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Types of roots:
Tap Root
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Plant structure that absorbs
water and nutrients,
anchors the plant, and
holds it upright
Go deep for water and
store nutrients (carrots,
dandelions, oak trees)
Fibrous Root

No single root bigger than
the others. Spread out just
under the surface to get
water quickly. (Grasses)
Other Root Types
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Adventitious Roots
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Aerial roots (air roots)
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Roots that form from parent
tissue other than root
tissue (Shoots, plant
cuttings)
Roots that allow plants to
climb and attach to rocks
(orchids)
Brace Roots

Roots that help to support
tall plants (buttresses, corn,
some trees)
Root Structure
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Root Hairs
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Vascular Cylinder
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Area that contains the xylem and
phloem
Apical Meristem
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Increase absorption by the root by
increasing surface area
Area where roots grow
New cells are fragile
Root cap
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Hard covering over end of root
Secretes slippery substance to allow
root to push through soil
Continuously losing and adding cells
1st Step
for
Water and Nutrient Transfer

Root Pressure

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One way movement of
water into roots
Caused by roots
pumping in minerals
Water follows the
minerals and can’t get
back out
Stems

Parts of the stem
 Node

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Internode

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Where the leaves are
attached
Region between
nodes
Bud

Contains
undifferentiated tissue
that will become a leaf,
flower, or branch
Mono vs Di

Monocot Stem

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Vascular bundle are
spread throughout the
stem
Dicot Stem

Vascular bundles form
a ring
Plant Growth
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Primary Growth
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Secondary Growth
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Growing wider
Tree Rings
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Elongating
Correspond to wet and
dry seasons
Ring a tree
Tree Layers
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2 layers of Bark
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Vascular cambium and
Sapwood
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Cork: outer layer containing
old phloem and filler cells
that have lots of fat and are
water proof
Cork Cambium: produces
cork
Where xylem and phloem
are
Heart wood

Contains old
nonfunctioning xylem that
helps support the tree
The End