Definition:
Gymnosperms (naked seed plants) are vascular plants (spermaphytes) whose bare seeds (unprotected) are borne on scales.
Angiosperms are also vascular plants whose seeds are enclosed in closed cavities giving later fruits.
The main characters in common (for gymnosperms and angiosperms) are the existence of roots and the presence of vessels (phloem and xylem containing tracheids, hence the name of Tracheophyta) ensuring the flow of sap.
Advantages of angiosperms and gymnosperms:
Angiosperms:
Stems, leaves and roots are internally traversed by the conductive tissues of raw and elaborate sap. Compared to the Gymnosperms, the Angiosperms manifest, from this point of view, the obvious advantage of a greater specialization of work: the conductive elements of the raw sap are perfect vessels.
In angiosperms, a fruit will form around the seed. The fruit will bring to angiosperms two big advantages:
* It will protect the seed against climatic hazards (drought ...).
* It will also promote the dissemination of seeds in the environment. .
The advantage of gymnosperms are:
* Development faster than angiosperms
* The role of support that is assumed, moreover, the areolated fibers of the Gymnosperms is here filled with fibers of sclerenchyma, sclerites, collenchym cells which have nothing of conductor.
* Pollination predominantly anemophilic
