Polystelic stem is seen in

Give scientific reasons: In pteridophytes,the development of the zygote inside the female gametophyte is considered an important phase.

Leaves that produce microspores and megaspores are called:

The stele is arranged in the form of a '$C$' in which portion of the fern plant $(Dryopteris)$?

In pteridophytes,reduction division occurs in .........?

In some pteridophytes, sporophylls form distinct compact structures called $A$ in $B$ and $C$. Here $A, B$, and $C$ refer to: