short
notes:
1-
The flower:
flower is defined a shighly condensed
and modified reproductive shoot. It has short or long flower stalk which is
called pedicel.
2-
Accessory leaf structures:
- Bract: The flower may arise in the
axial of leaf called brac.
- Bracteole: is a scale – like leaf found on the
floral stalk.
- Involucel: is a group of bracteiles
arranged in who rise on the floral axis as inumbellifera one or more whoris
just below a group of flowers. e.g, com positae.
Access
ory whoris:
- Caiya: it's the outer most whori of
green sepa is whose main function is the protection of the entire whoris.
- Corolla: it's the next whorie of
various colored petais.
4-
androecium:
it consists of collection of stamens
each stamen has a long slenjer filament with a bilobed a nther. Anthers produce
pollen grains for pollination.
5-
Gynoecium:
it's centrally located and consists
of a collection of carpels or pistils. Each carpel has three parts (ovary –
style – stigma).
6-
Calyx:
the outer most whore of flower. Each
member of this whorl is called sepal.
- When all the sepals are free from
each other it's called poly-sepalous.
- When the sepals are fused to each
other it's called gamosepalous.
- some time below calyx, a whorl
similar to sepals is found it's called epicalyx.
- Sometimes calyx is modified into
spines.
7-
Corolla:
The second whorl of flower is called
corolla each member of it's called petal.
- When the shape and size of petals
are similar it's called symmetrical.
- When they are not similar it's
called as symmetrical.
- When all the petals are free it's
called poly petalous.
- When petals are fused it known as
gamopetalous.
Zygomorphic
poly petalous corolla:
Papilionaceous five petals are present. It's posterior
petal is largest and known as standard. Standered covers two lateral petals
which are called as wings and two inner most basal petals are united to for
maker.
Perianth:
When there is no distinction between
calyx and corolla the whorl is described as perianth. Individual peroanth
segments are called tepals. Green tepals are called sepaliod and coloured
tepals are called petaloid.
Cohesion
of stamens:
When the floral parts of of similar
whorl are fused then it's called cohesion. When the stamens of an androecium
are free from one another, its called poly anjrous.
Diadelphous:
Filaments are united in two bundles
but the another remains free in these plants from 10 stamens, 9 stamens are
arranged in bundle while 1 remains free.
Adhesion of stamens:
When the stamens are attached to
other parts of flower, then it's called adhesion of stamens (Epipetalous –
Epiphyllous – Gynadrous)
Arrangement
of stamens:
- Diplostemonous: the stamens are
double number of petals and present in two whorls. The outer whorl of stamens
is alternating with petals.
- Obdiplostemonous: it's reverse of
stamen diplostemonous. The outer whorle of stamen is opposite to petals, while
inner whorl of stamen is alternating with petals.
- Haploste,onous: stamens are present
in single whorls. No of stamens is equal to no of sepals and petals and
generally whorl of stamens is alternating with petals.
Insertion
of floral leaves:
- Hypogynous flower: When petals
sepals and stamens are situated below the ovary in this condition ovary will be
superior.
- Perygynous flower: Receptacle grows
up wardly and form a cup shaped structure.
- Epigynous flower: The margin of
receptacle grows upwards enclosing the ovry completely and getting fused with
it, the other parts of flower arises above the ovary, the ovary is said to be
inferior.
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