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Stigma
Style Carpel Petal
Ovary

Sepal

Anther Stamen
Receptacle Filament

Structure of a Flower

Stamens are the third part of the flower from outside. A stamen has two parts

: anther and filament . The anther carries pollen grains which are generally
yellow in colour. An anther is held up by a thread-like part called the filament .

Pistil is the innermost part of the flower. The pistil has three parts : stigma ,
style and ovary. The stigma is the sticky surface at the top of the pistil. It traps

and holds the pollen. The style is the tube-like structure that holds up the

stigma. The style leads down to the ovary that contains ovule . The pollen
grains formed inside the anther move from the anther to the stigma. This

process is called pollination .
When a pollen grain lands on the stigma, a tiny tube grows from it and moves

down the style into the ovary. On reaching the ovary, it fertilizes the ovule.
Then, the ovule becomes the seed and the ovary becomes the fruit .

Seeds of a plant differ from the seeds of other plants in number, size, shape,

texture and colour.

STRUCTURE OF A SEED
Seed coat
Let us perform an activity to study the
internal and external structure of a Cotyledon
seed. All seeds have an external Shoot apex

covering called the seed coat . It is of Endosperm

different colours in different seeds. Its Root apex
function is to protect the seed.
Structure of a Seed
There is a scar on one side of the seed.

This is where the seed was attached to the plant. On the upper of the scar, you
will find a small hole. The seed absorbs water through this hole. The two parts

of the seed are called seed leaves or cotyledons . They store food for the baby
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