Transcript Specialized Roots

Roots

Just as important as stems and leaves….
Major Functions:
1. Serve as an anchor
2. Conduct nutrients and water
3. Store food
(ex. sweet potatoes, carrots, radish, turnip,
beet)
Root Functions

Root Development
Primary root develops from the
embryo
1. If primary root becomes the
main root=Taproot System
Root Development
2. If primary root stops growing
early on and new roots grow from
the stem, it is a Fibrous Root System

Fibrous vs. Taproot

Root Hairs
Grow from epidermal
cells of roots
Only occur in first ¼ of
root tip
Only live about 10
days
Absorb water and
nutrients from soil
particles
Function of Root Hairs

Root Hairs

Roots, Stems, Leaves,
Stomates….

 Transpiration: Pulling it all Together!
Food Storage Roots
Most roots store some
food
Some are enlarged to store
starch and other
carbohydrates
Examples: sweet potato,
carrot, beet, radish
Water Storing Roots
Produced by plants in arid regions
Can be quite large (159 lbs.!)
Examples: Manroot

Manroot
Grows close to ground: perennial vine
Roots can be several meters long and over
100lbs.

Pneumatophores

Extend above the surface of water for
plants that grow in swampy areas
Helps roots exchange gases
Example: Mangrove
Mangrove

Aerial Roots

 Roots that occur above the surface of the soil
 Examples: prop roots in corn (support in high wind)
Aerial Roots Continued

Adventitious roots in ivy for climbing
Poison Ivy

Contractile Roots
Help to pull the plant deeper into
the soil
Occurs from year to year
Examples: Lily, Dandelion
Parasitic Roots

Peg-like projections penetrate host’s
stem
Usually in plants that do not contain
chlorophyll (can’t make food)
Examples: pinedrops, dodder
(one organisms benefits, one is
harmed)
Pinedrops

Dodder: NO Chlorophyll
—Not green!
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Buttress Roots
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Huge roots near base of trunk
Usually in trees that grow in
shallow soil
Rainforest environments
Example: many tropical trees
Buttress Roots
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Buttress Roots
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Dicot Root Tip
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Cross Section of Root
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Modified Stems/Roots
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