The Pteridophytes include horsetails and ferns. Pteridophytes are used
for medicinal purposes and as soil-binders. They are also frequently grown
as ornamentals. Evolutionarily, they are the first terrestrial plants to
possess vascular tissues – xylem and phloem. You shall study more about
these tissues in Chapter 6. The pteridophytes are found in cool, damp,
shady places though some may flourish well in sandy-soil conditions.
You may recall that in bryophytes the dominant phase in the life
cycle is the gametophytic plant body. However, in pteridophytes, the
main plant body is a sporophyte which is differentiated into true root,
stem and leaves (Figure 3.3). These organs possess well-differentiated
vascular tissues. The leaves in pteridophyta are small (microphylls) as
in Selaginella or large (macrophylls) as in ferns. The sporophytes bear
sporangia that are subtended by leaf-like appendages called
sporophylls. In some cases sporophylls may form distinct compact
structures called strobili or cones (Selaginella, Equisetum). The
sporangia produce spores by meiosis in spore mother cells. The spores
germinate to give rise to inconspicuous, small but multicellular,
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