write characteristics of division
Pteridophyta
Answers
Answer:
Pteridophytes are non flowering plants (Cryptogams)...
Pteridophytes include Club mosses , horsetails , ferns etc....
➡These are first terrestrial plants to posses vascular tissue....
➡The main plant body of pteridophytes is sporophyte.It is differentiated into true roots,stem and leaves...
➡Pteridophytes are commonly called as Vascular cryptogams....
➡Roots are adventitious and stem is underground rhizome...
➡The leaves of pteridophytes are small(Microphylls)as in selaginella or large folds (macrophylls) as in ferns...
➡ Ferns show circinate vernation and the petioles are covered with brown multicellular hairs called Ramenta....
➡The stele may be prostele or siphonostele or solenostele...
➡One of the important characters of pteridophytes is that the sporophyte and Gametophyte are independent where as sporophyte is dominant,long lived whereas the gametophyte is reduced and short lived....
➡ Gametophyte is small , Short lived and it is produced from Haploid spores known as Prothallus....
➡ Sporophyte of the plant may be homosporous (all spores are similar) or heterosporous (Two different types of spores) i.e. microspores and megaspores...
➡Prothallus (gametophyte) are monoecious or dioecious...
➡Sex organs are Antheridia and Archegonia ,they are sessile....
➡Male gametes are Antherozoids formed from Antheridia...Antherozoids are uninucleate,spirally coiled ,biflagellate or multiflagellate structures....
➡ Union of male and female gametes results in Diploid zygote...Zygote develops into embryo...