ABC model of flower development
The ABC model of flower development is a scientific model of the process by which flowering plants produce a pattern of gene expression in meristems that leads to the appearance of an organ oriented towards sexual reproduction, a flower. There are three physiological developments that must occur in order for this to take place: firstly, the plant must pass from sexual immaturity into a sexually mature state ; secondly, the transformation of the apical meristem's function from a vegetative meristem into a floral meristem or inflorescence; and finally the growth of the flower's individual organs. The latter phase has been modelled using the ABC model, which aims to describe the biological basis of the process from the perspective of molecular and developmental genetics.
Flower of A. thaliana.
Flowers of A. majus.
Flowers of Petunia hybrid.
AGAMOUS mutation resulting in a double-flowered Arabidopsis
An inflorescence, in a flowering plant, is a group or cluster of flowers arranged on a stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a main axis (peduncle) and by the timing of its flowering.
Aloe hereroensis, showing inflorescence with branched peduncle
Amorphophallus titanum has the world's largest unbranched inflorescence. Photo of the plant in bloom in 2000 at Fairchild Tropical Botanic Garden in Miami, Florida, US
Ebracteate inflorescence of Wisteria sinensis
Bracteate inflorescence of Pedicularis verticillata.