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seeds of pteridophytes
no seeds
life cycle + generations of pteridophytes
haplodiplontic with the dominance of the sporophyte - while the gametophytes are greatly reduced in size and duration
asexual reproduction of pteridophytes
fragmentation of rhizomes (underground stems)
genus of ferns
polypodium vulgare
conspicuous plant body of ferns
sporophyte
classify ferns acc to types of spores
most -not all- homosporous
spores are produced by
meiosis of sporocytes in sporangia
gametophyte of ferns consists of
heart-shaped prothallus
gametangia of ferns : where?
antheridia and archegonia are grown on the underside of the gametophyte
fertilization in ferns (describe + type)
oogamy - flagellated sperms swim in a thin film of water to reach the neck of the archegonium - fertilizes the egg that remains attached to the prothallus
what happens to the prothallus later ?
withers and dies as the embryo develops into a mature sporophyte ( soon after reproduction)
the prothallus is the
gametophyte
why is the sporophyte of ferns considered dominant ? so ferns are classified as ?
larger and lasts longer - ferns are perennial (bc sporophyte lasts long)
genus of lycopodiopsida
selaginella
classify lycopodiopsida acc to type of spores
heterosporous
special characteristic of lycoposiopsida sporangia
grown in conelike strobilus
describe the stobilus of lycopodioposida
megasporangia on the lower megasporophylls - microsporangia on the upper microsporophylls
what about gametophyte formation in lycopodiopsida?
micro and mega sporocytes undergo meiosis - 4 spores (micro and mega) - gametophytes develop inside the sporangia (micro and mega too)
special development of gametophytes in lycopodiopsida
endoprothally - development of gametophytes within their respective spore walls
fertilization in lycopodiopsida cant happen unless
water carries the flagellated spores