Presence of megasporophylls leaves
Megasporophyll is a type of leaf-like structure produced by heterosporous plants such as seed plants, lycophytes, and some ferns. Generally, it produces megasporangia, sacs that produce megaspores of female spores. Moreover, in seed plants, ovule serves as the megasporangium.
Gymnosperms and fer pteridophytes are heterosporous eg. Selaginella are heterosporous i.e. forms micro and mega spores
The female sex organ is archegonia in both the groups.
The male gametes of Cycas and Ginkgo are motile like the pteridophytes.
Permanent retention of megaspores within the megasporangium.
Gametophytes are endosporic and highly reduced.
Female prothallus develops before fertilization and there is no free nuclear division.
Germination of spores is precocious in gymnosperms and heterosporous pteridophytes.
Development of distinct embryo after fertilization.
Like the pteridophytes , gymnosperms shows marked alternation of generation between sporophytic and gametophytic phase.
Sporophytic phase is dominant , independent and large at maturity while gametophytic generation shows progressive reduction between dependence.
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