ROOT

CHARACTERISTICS

—Located underground
—Shows positive geotropism
—Shows negative phototropism—Non-green, usually brown
— Branched or unbranched—Do not have buds
—Do not have nodes and internodes

FUNCTIONS

•Absorption of water and minerals
•Anchorage (support from the base)

TYPES

TYPE 1.-TAPROOT

When radicle germinated to form primary roots that are branched further into secondary and tertiary roots. E.g.- Dicot plants

TYPE 2.-FIBROUS ROOT

When radicle germinated to form much fiber like roots. E.g.- Monocot plants

TYPE 3.-ADVENTITIOUS ROOT

These roots arise from other parts of the plant rather than radicle. E.g.- prop roots in the Banyan tree

MODIFICATIONS

1.Storage root: They have reserve food

Conical- e.g.- carrot

Fusiform-e.g.- radish

Napiform-

e.g.- turnip, beat root

Irregular-e.g.- sweet potato

2. Prop roots:

e.g.- banyan tree
- They provide mechanical support
- Helps in the expansion of canopy

3. Stilt roots:

e.g.- sugarcane

- Stilt roots provide support from the base

4. Pneumatophores:

e.g.- mangrove trees
- These roots help in gaseous exchange

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