Biodiversity and bryophytes Flashcards
Niche
The role played by an organism
Ie.the sum of all it’s interactions with other organisms and it’s abiotic environment
Why are there more species in the tropics than temperate regions
Evolutionary lineage
More stable resources
Predation
Spatial heterogeneity
Are most abundant in habitats that are cool damp and shady
Bryophytes
Can bryophytes be aquadic
Yes
These are considered non vascular plants since they lack a true vascular system
They don’t have true xylem or phloem
But they do have what?
Bryophytes
Do have water conducting cells called hydroids in the center of there stems also food conducting cells called leptoidsthat surround the hydroids
Function of rhizoids
Only anchor plant don’t absorb water or inorganic ions
Most bryophytes grow in moist conditions because
They need either dew or rain water to reproduce
What is more conspicuous in bryophytes and ferns than in most plants or organisms
Alternation of generation
What is the most noticeable stage of bryophytes
Gametophyte stage (n) the “leafy” plant is the gametophyte generation that produces gametes.
In bryophytes the stage that is less noticeable is what?
The sporophyte (2n) that produces spores
What is different about the sporophyte and gametophyte stage of bryophytes?
There permanently attached which provides the sporophyte with nutrients
Bryophyte spores like those of all other plants are encased in a substantial wall impregnated with the most decay and chemical resistant polymer know as what
Sporopollenin sporopollenin walls enable bryophyte spores to survive dispersal through the air from one moist site to another.
Bryophytes can also reproduce asexually known as ?
Fragmentation (vegatative propagation)
Another wide spread widespread means of asexual reproduction in miss and liverworts would be the production of gemmae(multicellular bodies that give rise to new gametophytes)
Bryophytes have similar characteristics but based on there structure and reproduction they are separated into 3 groups what are they
Phylums
- Liverwort
- mosses
- hornworts
Hornwort
- only about 100 species
- sporophyte has a basal meristem and it’s growth is continuos
- a maturity sporophyte splits longitudinally into 2 ribbons
Liver wort
- Only about 6,000 species
- different in three ways from mosses and and horn worts including chemical,DNA, and morphological differences.
Third largest group (phylum) of bryophytes
Mosses
Lineages: peat moss , granite moss, true moss
Peat moss consist of one of the largest genus ?
Sphagnum more than 400 species are recognized of sphagnum
Among the sporophytes which genus has the most distinctive sporophyte ?
Genus sphagnum in within the peat mosses
Sphagnum has a very distinctive sporophyte because of it’s short stalk
The spore discharge in sphagnum is spectacular “makes little popping noises”
The operculum pops off it is attached to the pseudopodium “fake stalk”
Sphagnum gametophyte have what
Side branches which are more densely arranged near the top of the stem resulting in a mop-like head
- distributed worldwide
- primarily found in wet areas
- sometimes from floating mats over water
- contribute to the acidity of their own environment
Sphagnum
The old head of a person was conserved due to what ?
Acidity of a peat bog “sphagnum”
Why are peat bogs important?
Important to the global carbon cycle because peat stores (400 metric tons) of organic carbon that isn’t decayed to co2 by microorganisms
What is peat formed out of
Accumulation and compression of mosses also Sledges Reeds Grasses And other plants
