27 terms

Embryophytes- the land plants

traits of embryophtes
-alertnation of heteromorphic generations
-multicellular gametangia
-multicellular sporangia
-matrotophic embryo
-tough, decay resistant coat that surrounds land plant spores
sporopollenin function
-protection from dessication
-protection from disease
groups of land plants
-small embryophytes that lack vascular tissue, have a dominant gametophyte generation
bryophytes classified into three divisions
gametophyte body forms
-thallus=flattened disc or ribbon
-"stem-leaf" structure
-rhizoids anchor gametophte
sporophyte structures
-foot=embedded in gametophte
-sporangium=also called capsule in bryophtes
-species diversity (eighth)
-phylogenetic diversity
unique features of anthocerotophyta
-symbiotic relationship with nitrogen-fixing bacteria
-sporophte lacking a seta
-sporangium with basal meristem
gametophyte features
-chloroplasts=one per cell
-pyrenoids=starch organizing area
-ancestral features
-seta absent
-basal meristem (continuously produces new spores)
-species diversity (fourth)
hepatophyta unique features
-oil bodies in cytoplasm
-gemmae cups
-elaters in capsule
gametophyte differentiation
-complex thallus
-upper surface=pores, air chambers, photosynthetic tissue
-lower surface=rhizoids, anchor the thallus
-fertile brances bearing gametangia
-two kinds=archegoniophores, antheridophores
gemmae cups
-asexual propagules
-formed in gemmae cups
-splashed out of rain
-located under the surface of archegoniophore
-structure=foot, seta(short), capsule
sporophyte capsule
-filled with spores
-elaters= long skinny, twist in response to humidity to disperse spores
-species division (second)
-initial gametophyte growth phase
-structure=branching, green and photosynthetic, buds produce adult gametophytes
sphagnum- peat moss
-explosive dehiscence
-leaves with hyaline cells (large dead cells, barrel-shaped, fill with water)
sphagnum and acid
-hyaline cells=released phenols and tannins
-acid slows decompostion of organic material
-forms peat
-plant matter that accumulates under water-logged conditions and does not decompose
-1/3 or all terrestrial carbon locked in peat
peat uses
-wound dressing in WW1
-burned for fuel
dehiscence by peristome, capsule structure
-operculum:capsule lid falls off
-peristome:ring of teeth underneath operculum
perisotme mechanism
-peristome teeth
-move in response to humidity: close capsule when moist, open capsule when dry