Morphology of Flowering Plants

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Swollen roots for food storage: E.g. Tap roots of carrot, turnips and adventitious roots of

sweet potato and Asparagus.

Prop roots: Hanging structures that support Banyan tree.

Stilt roots: The supporting roots coming out of the lower nodes of the stem. E.g. Maize

& Sugarcane and Pandanus.

Pneumatophores: The roots that come out of the ground and grow vertically upwards

to get oxygen for respiration. E.g. Rhizophora growing in swampy areas. (AIPMT 2000)

3. FÜÑÇTÏØÑS ØF RØØT

Absorption of water and minerals

from the soil.

Provide a proper anchorage to the

plant parts.

Storage of reserve food material.

Synthesis of plant growth regulators.

THË STËM

It is the ascending

part of the axis

that develops

from the plumule

of the embryo of

a germinating

seed.

It bears

branches,

leaves, flowers,

fruits, buds

(terminal or

axillary), nodes

and internodes.

Nodes are the

regions of the

stem where leaves

are born.

Internodes are the

portions between

two nodes.

Young stem is

generally green

and later often

become woody

and dark brown.

1. FÜÑÇTÏØÑS ØF STËM



Spreading out branches bearing leaves, flowers and fruits.



It conducts water, minerals and photosynthates.



Food storage, support, protection and vegetative propagation

2. MØDÏFÏÇÅTÏØÑS ØF STËM

For food storage: E.g. Underground stems of potato, ginger, turmeric, zaminkand,

Colocasia etc. They also act as organs of perennation to tide over conditions

unfavourable for growth.

Stem tendrils: Slender and spirally coiled structures formed from axillary buds. They

help plants to climb. E.g. Gourds (cucumber, pumpkins, watermelon) & grapevines.

Primary Root

Tertiary Root

Secondary

Root