Green Plants Flashcards
LG 11-12
ecosystem services
all benefits that humans derive, directly or indirectly, from ecosystem fcns
nonvascular plant
paraphyletic group of land plants
- lack vascular tissue
- reproduce using spore
(ie) bryphytes
seedless vascular plant
have vascular tissue
- no produce seeds
- make microscopic spores that are carried by wind to new habitats
(ie) ferns
seed plant
have vascular tissue
- embryo w/ store of nutritive tissue surrounded by tough protective layer
(ie) angiosperm
vascular tissue
tissue that transports H2O, nutrients & sugars
- plants only
- made of complex tissues of xylem & phloem
- aka vascular tissue system
seed
plant reproductive system consisting of embryo, nutritive tissue (endosperm) & outer protective layer (seed coat)
angiosperm
flowering vascular plant that produces seeds w/in mature ovaries (fruit)
- form a single lineage
sporangia
spore-producing structure found in seed plants, some protists & some fungi
(ie) chytrids
gymnosperm
vascular plant that makes seeds but does not produce flowers
- 5 lineages: cycads, ginkgoes, conifers, redwoods, & gnetophytes
green algae
paraphyletic group of photosynthetic orgs
- contain chloroplasts similar to green plants
- often classified as protists
- closest living relatives of land plants
lichen
symbiotic association of a fungus
- a photosynthetic alga + cyanobacterium
peat
semi-decayed organic matter
- accumulates in moist, low-oxygen environments
rhizoid
hairlike structure that anchors nonvascular plant to substrate
roots
underground part of plant (anchors plants, absorbs H2O & nutrients)
- most ancestral branch in phylogenetic tree
rhizome
modified stem
- runs horizontally underground
- produces new plants @ nodes (sexual reproduction)
Types of green plants
(1) green algae
(2) land plants
Green plant significance to environment
(1) produce oxygen
(2) create, build, hold soil
(3) holds H2O & moderates climate (shade = low temp/wind)
(4) primary producers
3 categories of land plants
(1) nonvascular plants
(2) seedless vascular plants
(3) seed plants
cuticle
protective coating secreted by outermost layer of cells of animal/plant
- fcn: decrease water loss/evaporation
stoma
pore or opening
- (plants) microscopic pore surrounded by specialized cells that open pore -> found on surface of leaf/stem
- fcn: gas exchange
- pl. stomata
guard cells
1 of 2 specialized, crescent-shaped cells forming border of plant stoma
- change shape to open or close stoma
pore
(land plants) opening in epithelium
- fcn: gas exchange
lignin
substance found secondary cell walls of some plants
- stiff & strong
- complex polymer built from 6-carbon rings
- most abundant in woody plants parts
- hard to break
- “rings”
tracheids
(vascular plants) long, thin, water conducting cell
- has pits where lignin-containing secondary cell wall is absent
- allow H2O movement btwn adjacent cells
- “holes at top/bottom”
vessel elements
(vascular plants) short, wide, water conducting cell
- gaps through primary/secondary cell walls
- allow unimpeded passage of H2O btwn adjacent cells
“gaps at top/bottom”
wood
xylem resulting of secondary growth
- forms strong supporting material
- aka secondary xylem
gametangia
gamate forming structure found in all land plants, except angiosperms
- parts: antheridium (sperm-produce) & archegonium (egg-produce)
- gamate-forming structure of some chytrid fungi
- fcn: prevent drying out
embryophyte
plant that nourishes embryos inside own body
alternation of generation
(life cycle) alternate multicelluar haploid stage (gametophyte) w/ multicellular diploid stage (sporophyte)
- occurs in most plants, some protists
gametophyte
multicellular haploid form that arises from single haploid spore & produces gamates
- org undergoing AoG
sporophyte
multicellular diploid form that arises from 2 fused gamates to produce haploid spores
- org undergoing AoG
heterospory
(seed plants) production of 2 distinct types: microspores, which becomes male gametophyte & megaspores, which becomes female gametophyte
homospory
(seedless vascular plants) produce just one type of spore
microsporangia
(heterosporous plants species) a spore-producing structure
- produces microspores, which go onto develop into male gametophytes
megasporangia
(heterosporous plant species) a spore-producing structure
- produces microspores, which go onto develop into female gametophytes
pollen grain
(seed plants) male gametophyte enclosed w/in protective coat of sporopollenin
flower
(angiosperms) part of plant that contains reproductive structures
- includes: calyx, corolla & 1 or more stamens/carpels
petals
leaf-like organs arranged around reproductive organs of flower
- often colored & scented
- fcn: attract pollinators
pollination
process which pollen reaches carpel of flower, transferred from another to stigma, or reaches ovule directly
fruit
(angiosperm) a mature, ripened plant ovary + seeds + adjacent fused parts
- often fcns in seed dispersal
adaptive radiation
rapid revolutionary diversification w/in 1 lineage, producing many descendant species w/ wide range of adaptive forms
monocots
any angiosperm w/ single cotyledon (embryonic leaf) upon germination
- form monophyletic group
- aka monocotyledonous plant
dicot
any angiosperm w/ 2 cotyledons (embryonic leaves) upon germination
- no form monophyletic group
- aka dicotyledonous plant
plant adaptations
(1) water loss prevention
(2) UV irradiation protection
(3) upright growth - rigid outer layer, resist wind & gravity
(4) vascular tissue - lignin
(5) elaborate vascular tissue: tracheids & vessels
evolutionary innovations
(1) gametangium - no dry out
(2) land plant embryos - nourished by parent
(3) alternation of generation - meiosis
(4) gametophyte-dominated life cycle & sporophyte-dominated life cycle
(5) heterospory - 2 types of spores by diff. structures
(6) pollen - move gamates w/out water aid
(7) flowers - heterospory elaboration
(8) pollination by insects/animals
(9) fruit - part of ovary
