The document summarizes key aspects of plant inflorescence and flower structure. It describes that the arrangement of flowers on an axis is called an inflorescence. There are two main types of inflorescence - racemose, where the main axis continues to grow, and cymose, where the main axis terminates in a flower. A flower contains four whorls - calyx, corolla, androecium, and gynoecium. The androecium and gynoecium are reproductive organs, while the calyx and corolla are accessory organs. Flowers can be bisexual if they contain both male and female organs, or unisexual if they

2. 5.4THE INFLORESCENCE
 The arrangement of flowers on floral axis is called
inflorescence.
 A flower is a modified shoot wherein shoot apical
meristem changes to floral meristem.
 Two types of inflorescence are there depending on
whether apex gets converted into flower or
continues to grow:-
 Racemose:-main axis continues to grow
 Cymose:-main axis terminates in flower

4. 5.5THE FLOWER
 Flower has 4 different type of whorls arranged
successfully on stalk called thalamus or receptacle.
 4 whorls are calyx, corolla, androecium and
gynoecium.
 Calyx and corolla –accessory organ
 Androecium and gynoecium-reproductive organ.
 When flower has both androecium+gynoecium it is
bisexual.
 A flower having a stamen or a carpal is unisexual.

5. 5.5SYMMETRY OF FLOWER
 Flower may be actinomorphic (radial
symmetry)or zygomorphic(bilateral symmetry).
 When a flower can be divided into two equal
halves in radial plane-actinomorphic e.g.
mustard.
 When a flower can be divide into two equal in
vertical plane-zygomorphic
e.g,pea,gulmohar,bean
 If it cannot be divided into two equal halves by
any plane-asymmetric .eg canna

6. 5.5 TYPES OF FLOWERS
 Trimerous:-3 floral appendages
 Tetramerous:-4 floral appendages
 Pentamerous:- 5 floral appendages
 Bracteate:- flower with bracts .
 Ebracteate:-flower without bracteate.
 Based on position flowers are of following types:-
 Hypogynous:- gynoecium occupies highest position
and other all are below it. ovary in such flower is called
superior eg mustard.
 Perigynous:-gynoecium situated at the centre and other
part are located at rim of thalamus. Ovary here is half
inferior.
 Epigynous:-ovary here is inferior margin of thalamus
grows upward enclosing ovary and getting fused with it
eg, guava