Top 10 Facts About Pteridophytes! NEET | NTA NEET | NEET UG EXAM | BioLogical

NEET | NTA NEET | NEET UG EXAM | BioLogical

• The Pteridophytes include horsetails and ferns. 

• Evolutionarily, they are the first terrestrial plants to possess vascular tissues – xylem and phloem. 

• In pteridophytes, the main plant body is a sporophyte which is differentiated into true root, stem and leaves.

• The spores germinate to give rise to inconspicuous, small but multicellular, free-living, mostly photosynthetic thalloid gametophytes called prothallus. 

• The gametophytes bear male and female sex organs called antheridia and archegonia, respectively. 

• Water is required for transfer of antherozoids – the male gametes released from the antheridia, to the mouth of archegonium. 

• In majority of the pteridophytes all the spores are of similar kinds; such plants are called homosporous. Genera like Selaginella and Salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous. 

• The megaspores and microspores germinate and give rise to female and male gametophytes, respectively. 

• The female gametophytes in these plants are retained on the parent sporophytes for variable periods. The development of the zygotes into young embryos take place within the female gametophytes. 

• This event is a precursor to the seed habit considered an important step in evolution. The pteridophytes are further classified into four classes: Psilopsida (Psilotum); Lycopsida (Selaginella, Lycopodium), Sphenopsida (Equisetum) and Pteropsida (Dryopteris, Pteris, Adiantum)