Morphology of Flowering Plants

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Internodes do not elongate and the axis gets condensed.

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The apex produces different kinds of floral appendages laterally at

successive nodes instead of leaves.

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When a shoot tip transforms into a flower, it is solitary.

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The arrangement of cluster of flowers on the floral axis is called

inflorescence.

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Based on whether the apex gets converted into a flower or continues to

grow, inflorescences are of 2 types:

1.

Racemose: In this, the main axis continues to grow. Flowers are

borne laterally in an acropetal succession

2.

Cymose: In this, main axis terminates in a flower, hence is limited in

growth.

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Flowers are borne in a basipetal order (NEET 2013).

1. THË FLØWËR

1

3

5

7

2

4

6

It is meant for sexual reproduction.

Reduced leaf found at the base of the pedicel is called bracts. Flowers

with bracts are called bracteate and those without bracts, ebracteate.

Calyx & corolla are accessory organs, while androecium and

gynoecium are reproductive organs.

It is the reproductive unit in the angiosperms.

A flower has a stalk (pedicel). Its swollen end is called thalamus

(receptacle).

A typical flower has 4 kinds of whorls arranged on thalamus- calyx,

corolla, androecium & gynoecium.

In flowers like lily, the calyx and corolla are not distinct. It is

termed as perianth.

BÅSËD ØÑ SÝMMËTRÝ, FLØWËRS ÅRË ØF 3 TÝPËS

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Actinomorphic (radial symmetry): Here, a flower can be divided into 2

equal radial halves in any radial plane passing through the centre.

E.g. Mustard, Datura, chilli (NEET-II 2016).

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Zygomorphic (bilateral symmetry): Here, a flower can be divided into

two similar halves only in a particular vertical plane.

E.g. pea, gulmohur, bean, Cassia (AIPMT 2011)