What is the structure of ferns?

Fern is a plant with rhizome, adventitious roots and leaves. The stem contains both mechanical and conductive tissues containing tracheids and sieve cells.
The leaves (specifically in frond) are large, pinnately dissected, with a well-developed conducting system. The common leaf petiole is attached to the rhizome.
The leaves grow tops like stems, forming a “unfolding snail”. They perform the function of photosynthesis, gas exchange and sporulation.