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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)
Roots
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
Specialized Roots
Food Storage Roots Most roots store some
food
Some are enlarged to store starch and other carbohydrates
Examples: sweet potato, carrot, beet, radish
Produced by plants in arid regions Can be quite large (159 lbs.!) Examples: Manroot
Water Storing Roots
Grows close to ground: perennial vineRoots can be several meters long and
over 100lbs.
Manroot
Extend above the surface of water
for plants that grow in swampy areas
Helps roots exchange gases
Example: Mangrove
Pneumatophores
Mangrove
Roots that occur above the surface of the soil Examples: prop roots in corn (support in high
wind)
Aerial Roots
Adventitious roots in ivy for
climbing
Aerial Roots Continued
Poison Ivy
Contractile Roots Help to pull the plant deeper
into the soil
Occurs from year to year
Examples: Lily, Dandelion
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)
Parasitic Roots
Pinedrops
—Not green!
Dodder: NO Chlorophyll
Huge roots near base of
trunk Usually in trees that grow in
shallow soil Rainforest environmentsExample: many tropical trees
Buttress Roots
Buttress Roots
Buttress Roots
Dicot Root Tip
Cross Section of Root
Modified Stems/Roots