Write a note on Angiosperms.

(N/A) $\rightarrow$ In the Angiosperms or flowering plants,the pollen grains and ovules are developed in specialised structures called flowers.
$\rightarrow$ Seeds are enclosed by fruits.
$\rightarrow$ The angiosperms are an exceptionally large group of plants occurring in a wide range of habitats. They range in size from tiny,almost microscopic $Wolffia$ to tall trees of $Eucalyptus$ (over $100 \ m$) that grow in Australia.
$\rightarrow$ They provide us with food,fodder,fuel,medicines,and several other commercially important products.
$\rightarrow$ Classification of Angiosperms: Angiosperms are classified into two classes:
$(i)$ Dicotyledons and $(ii)$ Monocotyledons.
$(i)$ The Dicotyledons: There are two cotyledons in the seeds of dicotyledons. Leaves possess reticulate venation and flowers are tetramerous or pentamerous (meaning there are four to five members in each floral whorl).
$(ii)$ The Monocotyledons: There is only one cotyledon in the seeds of monocotyledons. Leaves possess parallel venation and flowers are trimerous (meaning there are three members in each floral whorl).
$\rightarrow$ The male sex organ in a flower is the stamen. Each stamen consists of a slender filament with an anther at the tip. The anthers,following meiosis,produce pollen grains. The pistil consists of an ovary enclosing one to many ovules,a style,and a stigma.