[plants]: pteridophytes Flashcards
pteridophytes include
horsetails and
ferns
uses of pteridophytes
medicinal purposes
soil binders
ornamentals
evolutionary significance
first terrestrial plants
first to possess vascular tissues
first to possess true roots, stems,leaves
first to incorporate endosporic development
habitats
cool shady places
sometimes even on sandy soil
main body is
sporophytic in nature
the leaves in pteridophyta are
microphylls(small; like in selaginella)
macrophylls(large; like in ferns)
the sporophytes bear
sporangia
that are subtended by leaf-like appendages
called sporophylls
in some cases, sporophylls may
distinct
compact
structures called strobili or cones
eg: selaginella, Equisetum
the sporangia produce spores by
meiosis in spore mother cells
the spores germinate to give rise to
inconspicuous small multicellular free-living mostly photosynthetic thalloid gametophytes called prothallus
the prothalli require (habitat)
cool damp shady places to grow
due to the limitation of habitat adaptation
pteridophytes are distributed to only certain narrow geographical regions
sex organs in pteridophytes
antheridium
archegonium
_____ is required for fertilisation
water
zygote produces
sporophytic body
homosporous
morphologically similar spores which facilitate isogamy
heterosporous
morphologically dissimilar spores which failitate heterogamy
megaspore and microspore germinates to give rise to
female and male gametes respectively
the gametophytes in these plants
are retained for variable periods on parent sporophytic body
the development of zygotes
takes place within the female gametophytes
this event is a precursor to seed habit
classes of pteridophytes
psilopsida
pteropsida
lycopsida
sphenopsida
ex of psilopsida
psilotum
ex of lycopsida
selaginella
lycopodium
ex of sphenopsida
equisetum
ex of pteropsida
pteris
dryopteris
adiantum
