Green Plant Phylogeny/Life Cycle (Final Exam) Flashcards
Chlorophyte branch =
chlorophyceae + ulvophyceae
streptophyte branch =
streptophyte algae + embryophytes
chlorophyceae roots =
symmetrical flagellar roots
chlorophyceae dominant ploidy
haploid dominant
chlorophyceae can be
unicellular, colonial, and multicellular algae
some chlorophyceae are
terrestrial algae
Ulvophyceae roots =
symmetrical flagellar roots
Ulvophyceae marine groups have
an isomorphic alternation of generations
Ulvophyceae freshwater groups have
a haploid dominant life cycle
Ulvophyceae forms =
Multicellular forms as well as siphonous (coenocytic)
Streptophyte Clade includes
several basal clades and also land plants
Streptophyte Clade/groups ploidy
a haploid dominant life cycle
Streptophyte Clade/groups developed _____ & ______
oogamy
& sporopollenin = Desiccation and decay resistant
(Streptophyte Clade/groups) precursors to land plants developed
a heteromorphic alternation of generations
nonvascular plants =
basal groups of embryophytes
nonvascular plant group is a
paraphyletic group
nonvascular plants all lack
X & P
nonvascular plants all have dominant…
(long-lived) gametophyte generations
nonvascular plants all disperse
spores long distances
nonvascular plants all have sperm that
swim short distances
Liverworts aka
Marchantiophyta
Liverworts are the
oldest extant lineage of embryophytes
liverworts have no (2)
stomates
IAA (auxin)
liverworts consist of 2 main growth forms:
thallus
leafy
liverworts reproduction (2)
- asexual (break apart + gemmae)
- sexual (antheridiophores + archegoniophores + moss-like sporophytes)
hornworts aka
anthocerophyta
hornworts are thallus plants with
long sporophytes with indeterminate growth (open like a bean)
hornworts have
stomata on sporophytes
hornworts have fewer
species than other nonvascular plants (100)
hornworts use
N-fixing bac in thalli
mosses aka
Bryophyta
mosses are generally
leafy
most basal moss group
sphagnum mosses
sphagnum mosses have
dead cells for water storage
“true” mosses typically have (3)
a sporophyte like Mnium
capsule w/ peristome
hardum-vascular strand w/ hydroids & leptoids
seedless vascular plants =
basal vascular plants
what type of group are seedless vascular plants
paraphyletic
all seedless vascular plants have xylem with
lignified tracheids
all seedless vascular plants have phloem with
sieve cells
all seedless vascular plants have dominant
sporophyte generation
all seedless vascular plants have
free-living gametophytes
all seedless vascular plants disperse
spores long distances
all seedless vascular plants sperm
swim short distances
cooksonia =
early vascular plant
cooksonia roots –>
none
cooksonia have terminal
sporangia
cooksonia stele =
protostele
cooksonia exhibit
dichotomous branching
lycopodiophyta exhibit
dichotomous branching
lycopodiophyta stele =
protostele
lycopodiophyta leaf like structures are
microphylls = one vascular bundle in leaf
lycopods are
homosporous = producing only one kind of spore (no sex diff)
lycopods lack
ligules (narrow blades like grass)
lycopods =
most basal extant lycopodiophyta
selaginella =
more derived extant lycopodiophyta
selaginella are
heterosporous (producing diff sex spores)
selaginella have
legumes
lycopodium cernuum lives in
Hawaii
lycopodium cernuum branches
dichotomous
lycopodium cernuum has
cones (strobili) at the tips of some of its branches
lycopodium cernuum the leaves in the strobili are
sporophylls
Lepidodendron are
heterosporous
Lepidodendron produces
wood but no 2* phloem
Lepidodendron female gametophyte are
seed-like, bigger than your thumb
Lepidodendron dominated
early coal forests (30 m tall)
Lepidodendron became extinct as
earth began to dry
Monilophytes =
ferns &; their relatives
Monilophyte group generally have (2)
- megaphylls (euphyllophytes / leaves with branched vascular bundles)
- siphonostele (not all of them)
Monilophytes evolved before
carboniferous period
in vascular plants –>
sporangia are produced by sporophylls
Leptosporangiate ferns have
Leptosporangia = each sporangium comes from one cell
ferns =
leptosporangiate ferns + eusporangiate ferns
eusporangiate ferns have
eusporangia = each sporangium arise from several cells
leptosporangiate ferns leaves are
large (double for photosynthesis and as sporophylls)
leptosporangiate have loads of
sporangia on sori or other groupings
leptosporangiate stems are
usually stems, but some ferns have long, upright shoots
leptosporangiate venation =
circinate
psilotales aka
whisk ferns
psilotales exhibit
basal vegetative traits
psilotales branching =
dichotomous
psilotales stele =
protostele
psilotales leaves =
enations (leaves)
psilotales have no
roots (instead, symbiotic fungi)
psilotales synangia comprised of
3 sporangia
psilotales have some
gametophytes that are subterranean
equisetales aka
horse tails
equisetales have
hollow stems
equisetales stele
eustele
equisetales exhibit
small, dead leaves (actually macrophylls)
equisetales have terminal
strobili (homosporous & silica rich)
prior to seed evolution: (2)
esteles evolved
bifacial vascular cambium
spermatophytes aka
seed plants
why the spermatophyte name?
sperm = seed
spermatophytes have dominant
sporophyte
spermatophytes house
female gametophyte and developing embryo on parent plant (not free-living)
spermatophytes female gametophyte…
no longer separated from sporophyte (housed on ovule)
spermatophytes pollen grain =
immature male gametophytes
spermatophytes male & female gametophytes are
extremely reduced in size
- fewer cells
spermatophytes male gametophytes are
made up of 3 cells
spermatophytes male gametophytes pollen is
surrounded by sporopollenin
in the nonvascular and seedless vascular plants, sporopollenin was
in the walls of spores
spermatophytes allowed
migration to drier habitats (important during drying of the Permian)
Seed Plant (Gymnosperm) Ovule Development
Only one megaspore (n) develops from megaspore mother cell (2n); the 3 other cells from meiosis die
male gametophytes are produced by
microspores
Cycadophyta evolved
280 mya
Cycadophyta dominated during
Triassic, Jurassic, and Cretaceous
Cycadophyta are
dioecious (male and female plants)
Cycadophyta have
flagellated sperm
Cycadophyta male cones
are persistent
Cycadophyta female cones
usually break apart
Cycadophyta leaves are
evergreen
Ginkgophyta only have
1 extant species
Ginkgophyta exhibit
fleshy seeds (seed coat has several layers)
Ginkgophyta are
dioecious
Ginkgophyta have no
persistent “cones” (strobili)
Ginkgophyta have
flagellated sperm
Coniferophyta is the most
species group of gymnosperms
Coniferophyta female cones (strobili) are
persistent
Coniferophyta sperm are
not flagellated
Coniferophyta are typically
evergreen trees and shrubs
Coniferophyta are mostly
monoecious (some dioecious; Podocarpus)
Coniferophyta are the most…
successful phylum outside of the Angiosperms in temperate regions
Gnetales are
in or sister to Coniferophyta
Gnetales were once considered
the sister group to the flowering plants
Gnetales = most…
diverse group morphologically
Gnetales strobili
if present, very flower-like
- nectar
- few parts
- 1 seeded
Gnetales exhibit
vessels!
Ginkgophyta seed coat with
several layers (fleshy outside / hard inside)
Ginkgophyta were never
dominant
Southern Hemisphere conifers =
dioecious (male & female cones on same plant)
Northern Hemisphere conifers =
monoecious