seedless vascular plants Flashcards
vascular plants that don’t produce seeds:
club mosses (lycophytes) and ferns
dominant generation:
sporophyte body, is larger and more branched, becomes independent, main photosynthetic plant, produces multiple sporangia
what vascular tissue arises?
tracheids, true stems, leaves, and roots
leaves of vascular plants:
have veins, bilateral symmetry, definite stem arrangement, determinate growth, divide into microphylls and megaphylls (lots of branching)
how do megaphylls develop
more photosynthetic tissue around veins, megaphylls combine the microphylls
spore function
dispersal
gametophyte/sporophyte relation
independent gametophyte, dominant sporophyte
when did lycophytes, pteridophytes, and progymnosperms dominant
carboniferous period 360 million years ago
club mosses -
don’t produce eggs and sperm, produce spores that get released into atmosphere. only 1000 species,
have microphylls (leaf with one vein),
homosporous (gametophyte produces male and female)
hetrosporous (produces microspore which is male gametophyte and megaspore which produces egg)
clustered sporangia
club moss life cycle:
spore grows into gametophyte, eggs and flagellated sperm produced through mitosis, fertilization produces sporophyte, which eventually results in a strobilus
spike moss -
heterosporous, two different types of spores, sporangia on undersisdes of leaf, spores released to produce microspores and megaspores, strobilus = cone
sole genus of spike moss
selaginella
resurrection plants -
can rehydrate themselves, spike moss is an example
quillworts -
mostly aquatic and semi aqautic, heterosporous, sporangia found at the base of the root
pteridophyta -
ferns, horsetails, whisk ferns
have many sporangia that form clusters
fern life cycle -
homosporous or heterosporous, frond is the photosynthetic part, sori are clusters of sporagnia, heart shaped gametophyte (prothallus) megaphyll leaves
young frond
fiddlehead
parts of a frond -
stipe (stem), blade (lamina), rachis (midrib of blade), pinna (leaflet), costa (midrib of pinna)
have three levels of division (tripinnate)
sterile or fertile (contain sori)
how do ferns release spores -
they dry up and break open, sporangia held together by annulus or indusium
false indusia -
part of blade material is flipped over
sensitive ferns
sterile fronds die right away
types of ferns
marsilea - water fern, frond has four parts
azolla- has pockets of cyanobacteria
cyathea - tree fern
problematic ferns
bracken and giant salvinia
horsetails
have modified leaves (megaphylls), have strobili that produce spores, stems have silica deposits, megaphylls are reduced, can have whorled branches or unwhorled branches
spores produced by meiosis contain elaters
whisk fern -
include psilotum and timesipteris, don’t have true roots or leaves, have rhizoids, enations (scales) are present, sporangia form clusters of three
psiloutum gamteophyte characteristic
relies on endophytic fungus