Distinguish between the bryophytes and ferns Identify features of the nonvascular plants Identify features of the seedless vascular plants Identify features that distinguish plants from algae Describe the relationship between sporophytes, gametophytes and alternation of generations Describe ecological and economic roles of bryophytes and ferns
15,000 species (mosses)
Apical meristem in key resource-finding locations
central spot from which all cells divide, mitosis takes place here alternation of generation more developed
the moss we see is diploid of haploid?
the visible trend with sporophytes and gametophytes
Embryos dependent on female parent plant (similar to placental mammals)
"Embryophytes"...not free living
does algae have embryophytes?
other gymnosperm info
Waxy cuticle that prevents drying Secondary metabolites (products of pathways that are side branches off main metabolic pathways)...used for defense...algae don't do that!
Bryophytes (liverworts, hornworts, mosses)
location: light but not direct sun, shady, wet, etc characteristics: bright green, always small
can't transport water any distance, not structure, so they're small
asexual reproduction: little gemma cups of genetic material splashed out
sexual reproduction for gametophytes
palm-tree like structure archegonium: produce egg antheridium: produce sperm MUST BE: submerged in water for sperm to swim to egg
more moss info:
Location: Moist forests and wetlands Even found in extremely dry climates as long there is water at critical time "Feathery" or "cushiony" Characteristics: No vascular tissue (no capacity to transport water) Small (do you see a connection here?) Dominant gametophyte Usually only a few cells thick, with no cuticle Anchored by rhizoids (root-like structures...no way to absorb water)
all mosses must have _____ for fertilization
once germination begins, a plant must have....
Ecological role of bryophytes
Form microhabitats for animals Carbon reservoirs in peat bogs store carbon dioxide and help to stabilize global CO2 levels Ecological "barometers"...mosses very susceptible to toxins/pollution
Economic role of bryophytes
Soil conditioner Peat is source of fuel Packing material Mosses and liverworts in greenhouses...like a weed...can quickly cover flats of seedlings
what about peat bogs make them great for preserving tissue?