C9L3P3
Plant Organs
Roots
Types of organs in plants
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Roots
Stems
Leaves
Roots
Roots anchor a plant, either in soil or onto
another plant or an object such as
a rock.
All root systems help a plant absorb water
and other substance from the soil.
Functions of Roots
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Anchors
Absorbs
Transports
Stores food
Roots
Roots are the organs of
the root system.
A root system is all the
roots of a plant.
Two Types of Root Systems
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Taproots
Fibrous roots
Taproots
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commonly found in
dicots
penetrates the
soil with very
little branching
often stores food
(fleshy roots)
Taproots
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has one or a few
main roots that are
thicker and longer
than the other
roots of the plant
examples: carrots
and dandelions
Fibrous Root System
 commonly
found
in monocots
 have no main
section but
branch out into
the soil in all
directions
Fibrous Root System
 Has
a cluster of
roots that are
approximately
equal in size
 They branch
several times
 Example:
grasses
Parts of the Root
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Root cap – dead, thick-walled
cells; for protection
Epidermis - outer covering for
protection, one cell layer thick
Root Hairs - long, fingerlike
projections of root's epidermal
cells that greatly increase the
root's water-absorbing surface area
Parts of the Root
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Xylem: has long, thick-walled cells which
carry water and dissolved minerals
upward (from roots up to stem and the
leaves)
Phloem: has cell walls, slightly thinner
then xylem; it carries water and dissolved
foods downward
Xylem and Phloem

Water-conducting System (located near
the center of the root)
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Xylem and phloem are usually arranged
in fibrovascular bundles.
fibrovascular bundle
xylem and
phloem
surrounded by
supporting
tissues; found in
non-woody plants
fibrovascular bundles
Xylem and Phloem
Root Structure
Dicot Root
Monocot Root