a ppt on inflorescence class 11 biology done by:Wajiha waseem

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