Morphology of Flowering Plants
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Generally, sepals are green, leaf-like and protect the flower in the bud
stage.
The calyx may be gamosepalous (sepals united) or polysepalous
(sepals free).
B. ÇØRØLLÅ
It is the whorl inner to calyx. It is composed of petals.
Petals have bright colour to attract insects for pollination.
Corolla may be gamopetalous (petals united) or
polypetalous (petals free).
Shape and colour of corolla vary in plants. Corolla may be tubular, bell-
shaped, funnel-shaped or wheel-shaped.
The mode of arrangement of sepals and petals in floral bud is called
aestivation.
3. TÝPËS ØF ÅËSTÏVÅTÏØÑ
Valvate: Sepals or petals
in a whorl just touch one
another at the margin,
without overlapping. E.g.
Calotropis.
Twisted: One margin of
the appendage overlaps
that of the next one and
so on. E.g. China rose,
lady’s finger & cotton.
Imbricate:
Margins
of
sepals or petals overlap
one another but not in any particular direction. E.g. Cassia & Gulmohur.
(NEET 2014)
Vexillary (papilionaceous): In pea & bean flowers, there are five petals;
the largest (standard) overlaps the two lateral petals (wings) which in
turn overlap the two smallest anterior petals (keel). (NEET 2016)
Ç. ÅÑDRØËÇÏÜM
The male reproductive part is composed of stamens.
Each stamen represents the male reproductive organ. It
consists of a stalk (filament) and an anther.
Each anther is usually bilobed. Each lobe has 2 chambers,
the pollen-sacs.
The pollen grains are produced in pollen-sacs.
Valvate
Imbricate
Types of aestivation in corolla
Twisted
Vexillary
Corolla
Androecium