Land Plants Flashcards
Land plants probably originated from _____________ as evidence of nonvascular
plants evolved during the Silurian but the earliest fossils of nonvascular plants
are from the Lower Devonian.
green algae
Plants became independent from their aquatic habitats from the development
of
vascular tissues.
Period was a period of rapid plant diversification, characterized by the
appearance of seed-bearing plants and the first forests.
Devonian
Mesozoic terrestrial ecosystems were dominated by
conifers, cycads, and
ferns
diversified spectacularly in the Cretaceous and are the most
abundant group of plants
Flowering plants
The fossil record of plants is typically
fragmentary
Other plants become broken up or fragmented due to
taphonomic processes
Plant material may also be preserved as
molds
or casts.
There are three important groups of Nonvascular plants all of which are extant:
Hornworts, Liverworts, and Mosses.
Similar to liverworts but sporangia are able to grow continously; Early Devonian-Recent
Nonvascular plants(hornworts)
Small plants with a flattened leaf-like body(thallus); Late Devonian-Recent
Hepatophytes(liverworts)
Filamentous mat with simple leaves and root-like structures (rhizoids)
Bryophytes(mosses)
Seedless vascular plants
include three extinct groups,
and three groups with living
relatives:
Club mosses, Ferns,
and Horsetails.
Extinct plants with dichotomously branched, simple axes. Sporangia terminal; Silurian-early Devonian
Rhyniophytes
(Cooksonia)
Leafy plants with sporangia on upper surface of leaves or at the leaf-stem intersect; Late Silurian-Recent
Lycop hytes
(club mosses)
Extinct dichotomously branched plants,
sometimes with spiny axes. Sporangia
on side of axes; Early-late Devonian
Zosterophylls
(Sawdonia)
Extinct fern-like plants with woody tissue; Mid-Upper Devonian
Progymnosperms
(Archaeopteris)
Vascular seeded plants are
divided into plants with naked
seeds,______and
plants with seeds enclosed by
fruit,___________
the gymnosperms,
the angiosperms.
Large-leaved plants with sporangia on the
lower surface; Mid-Devonian-Recent
Pteridophytes
(ferns)
Plants with leaves and branches fused in
whorls. Fertile branches have terminal cones ; Late Devonian-Recent
Sphenophytes
(horsetails)
The most important
groups of Gymnosperms
are the
Conifers, Cycads,
and Ginkgoes.
are the flowering plants, the
dominant living flora.
Angiosperms
Fern-like plants with spores on the leaves; Late Devonian-Jurassic
Seed ferns
Woody trees with needle or scale-like leaves. Seeds in cones; Early Carboniferous-Recent
Conifers
Woody, stemmed plants with palm- or fern-like leaves and cones; Early Carboniferous-Recent
Cycads
Extinct plants that resemble cycads but have flower-like cones; Triassic-late Cretaceous
Bennettitales
(Cycadeoidea)
Woody trees with fan-shaped leaves.
Cones absent; Late Triassic-Recent
Cinkgoales
(ginkgoes)
Unusual group with cone clusters resembling flowers; Late Triassic-Recent
Cnetales
(gnetae)
Plants with flowers. Seeds enclosed within a fruit; Cretaceous-Recent
Angiosperms
(flowering plants)
Two morphologically distinct vegetative phases can exist in plants
the gametophyte and
sporophyte stages.
THE OLDEST FOSSILIZED NONVASCULAR PLANTS ARE_________ DESCRIBED FROM THE LOWER DEVONIAN OF BELGIUM
LIVENVORTS
THE OLDEST
TRUE VASCULAR PLANT IS
COOKSONIA
ADVANCED SPORE- BEARING PLANTS WITH TRUE LEAVES AND ROOTS EVOLVED
DURING THE DEVONIAN
LYCOPODS (CLUB MOSSES), SPHENOPHYTES(HORSETAILS),
PTERIDOPHYTES (FERNS), AND PROGYMNOSPERMS(PRECURSORS TO THE SEEDBEARING GYMNOSPERMS).
are those
plants with exposed seeds.
Gymnosperms
those plant
that flower and produces
seed within the fruit.
Angiosperms-
their internal structure
is very different with
spore-bearing ferns
Probably developed
from
progymnosperms
are a group of cone-bearing seed plants, a subset of gymnosperms.
mainly occupy dry environments and were the most important plants during Carboniferous and the Permian
Period.
Conifers
is an important genus of extinct gymnosperms, related to or representing the earliest conifers. This was very distinctive upper paleozoic coniferophyte
Cordaites
have large and compound leaves like ferns and palms. The stems or trunks are usually unbranched and covered with
scalelike leaf bases
Cycads
are large, densely branched trees with
entire or bilobed leaves. Fossil ginkgo
leaves closely resemble the modern foliage.
Gingkoes
refers to an order of seed plants that include three families:
Gnetaceae, Welwitschiaceae, and Ephedraceae T they might share a common ancestor with the angiosperms
Gnetales
Sphenophyte
Carboniferous
is the stem remains of the extinct giant horsetail, although it is commonly used to describe the entire plant. usually preserved
as Cast. The figured stem fragment is 18 cm in length
CALAMITES
Lycophyte
Carboniferous
it is part of the rootstock on which the massive trunk of the fossil lycopod, Lepidodendron rested. it is horizontal, branched, underground axes with small root-like appendages Length figure is 15
cm
STIGMARIA
Sphenophyte
Carboniferous-Permian
is foliage associated with the giant horsetail Calamites. has slender leaflets with approximately 4cm height Individual leaves were fused at their bases and have a
single, unbranched vein running along
the length of the leaf
ANNULARIA
Upper Carboniferous
Foliage associated with the horsetail Sphenophyllum (a sphenophyte). Contemporary with the giant horsetails, these forms were similar to the modern herbaceous species, Equisetum.
Whorls of wedge-shaped leaflets encircled the slender stems. Leaflets had dichotomously branched veins and were
approximately 1 cm in length.
SPHENOPHYLLUM
Lacophyte
Carboniferous-Permian
Is a genus of extinct spore bearing arborescent lycophyte. Figure stem fragment is 6cm in length
Sigillaria
Pteridophyte
Devonian-Permian
Part of the foliage of the extinct fern Sphenopteris Fronds have
distinctive lobed pinnules. The figured section of frond is 6 cm in length
Sphenopteris
Lycophyte
Upper Carboniferous
Section of a branch showing the
characteristic pattern of Lepidodendron leaf bases. leaves have linear with a swollen
attachment area. leaf size varied
between species, and mainly restricted to smaller branches
Leaf cushions are approximately 3 cm in length
LEPIDODENDRON
Seed Fern
Upper Carboniferous
Frond of Mariopteris
were generally small
(50cm in length) and
some specimens had
thread-like tendrills at
the leaftips
MARIOPTERIS
