Lecture 20 Flashcards
what are the novel features of vascular plants?
- Embryo: zygote retained, nourished by gametophyte (matrotrophy)
- Cuticle
- Sporopoleninwalled spores(decay resistant)
- Antheridia & Archegonia with sterile jacket
- Sporiclife cycle
- (Stomata)
- Branching Independent Sporophyte
- Vascular Tissue (xylem & Phloem)
when did vascular plants first appear in the fossil record?
400 million years ago
describe early vascular plants
Earliest vascular plants were the size of trees! The dominant forests on earth.Carboniferous swamps are the source of most coal deposits.
do tracheophytes have vascular tissue?
yes
do tracheophytes have true leavs?
yes
do tracheophytes have true roots?
yes
what is the life cycle of a tracheophyte?
independent sporophytes
what are the types of steles?
protostele, siphonostele, and eustele
structures of a protostele
Solid core
•Xylem in center
•Phloem Surrounds xylem
•No leaf gaps
structure of a siphonostele
- Pith in center.•“solid” ring of vascular tissue.
- Phloem on outside
- Phloem both inside & outside.
- Xylem in middle of band.
- Leaf gaps present
structure of a eustele
- Discrete bundles
- Vascular Tissue in discrete bands
- No leaf gaps.
- Leaf trace gaps instead.
describe a microphyll
- Single vascular trace without a leaf gap.
- Derived from outgrowth of stem.
- Usually smaller
describe a megaphyll
- Vascular trace leaves a leaf gap in stele.
- Multiple branching veins (usually).
- Derived from branches via planation and webbing.
- Usually larger
what are the types of leaves of tracheophytles?
microphyll and megaphylls
how did microphylls evolve?
- Originated as outgrowths of the stem.
- Enationswith no vascular tissue.
- Then evolve vascular tissue in core.
how did megaphylls evolve?
•Derived from branches via planation and webbing.
what kind of life cycle do seedless vascular plants have?
sporic life cycle
describe the sporophyte of a seedless vascular plant
they are free living and dominant
describe the gametophyte of a seedless vascular plant
it is free living and deduced
do seedless vascular plants require water for fertilization?
yes
describe the sporophyte phase of seedless vascular plants
The sporophyte phase has true leaves, stems, roots (they contain vascular tissue).
list the different families of lycophytes
- Lycopodiaceae
- Selaginellaceae
- Lepidodendrales*
- Isoetes
what are the characteristics of lycophytes?
- Microphylls
* Protostelein root and shoot
what family do club mosses belong to?
lycopodiacea
how many species are found in club mosses
400 species
what kind of stele do club moss have
protostele (in both stem and root)
what kind of leaves do club mosses have?
microphylls
describe the sporophyll of club mosses?
Sporophylls with adaxial sporangia
describe the location of Adaxial Sporangia
-Attached to upper surface of microphyll.(sporophyll) and attached to the bottom of a megaphyll
describe the location of terminal sporangia
-Develop at the tip of a branch
what are strobili?
aggregations of sporophyll
are sporophytes or gametophytes dominant in the lifecycle of a lycopodiaceae?
the sporophyte is dominant
are the sporophytes or gametophytes of a lycopodiaceae independent?
they are both independent
are the gametophytes of lycopodiacea photosynthetic or nonphotosynthetic?
they can be both
how long does it take for lycopodiaceae to mature?
6-15 years
how many species are there in the salaginellaceae family?
750 species in Genus Selaginella
are Selaginellaceae heterosporous
yes
what kind of stele do Selaginellaceae have?
they have a protostele in their stem and root
what kind of leaves do Selaginellaceae have?
microphylls
what kind of sporangia do Selaginellaceae have?
adaxial sporangia
what kind of sporphylls do Selaginellaceae have?
megasporphyll and microsporophyll
do Selaginellaceae have strobili
some do
what is an example of Selaginellaceae
resurrection plant
what does it mean for something to be homosporous?
Equal size sporesAll small
what does it mean for something to be heterosporous?
Unequal size spores.
Some large.
Some small
(meaning that it has mega and microsporangia)
what does heterospory lead to
the separation of male and female gametophytes
what are microspores? what is their function? what is their gender?
they are microgametophytes
they are male
they produce sperm
what are megaspores?
what is their function?
what is their gender?
they are megagametophytes
they are female
they produce eggs
ligule
scalelike outgrowth at base of microphyll or sporophyll. Note: microsporphylls & megasporophylls can occur on same strobilus.
are megagametophytes unicellular or multicellular
multicellular
where do megagametophytes develop
inside megaspore wall
what do megagametophyte form?
archegonia
do megagametophytes have chlorophyll?
no
are microgametophyte unicellular or multicellular?
they are multicellular
where do microgametophytes develop?
inside of a microspore
what do microgametophytes produce?
antheridium
do microgametophytes have chlorophyll?
no
what family do quill warts belong to?
isoetaceae
how many species of quill worts are there?
150 species
are quill worts homo or heterosporous?
heterosporous
what kind of stele do quill worts have?
protostele
what kind of stem to quill worts have?
a corm
true or false, quill worts have ligule
true
what kind of habitat do quill worts live in?
mainly aquatic
what kind of photosynthesis do quill worts undergo?
CAM photosynthesis
what family of lycophytes are extinct?
lepidodentrales
when did the lepidodentrales live?
362-290 million years ago
where did lepidodentrales
coral forming swamps
how tall did lepidodentrales grow?
10-35m tall
did lepidodentrales undergo secondary growth?
yes in the cortex
did lepidodentrales have secondary vascular tissue?
no
