Download K: Plantae Div: Filicophyta (Div: Pterophyta)

K: Plantae Div: Filicophyta
(Div: Pterophyta)
1. True vascular plant that have large leaves (fronds) with branching
vascular strands (veins).
2. Sporophyte (2n) plant body large; gametophyte (n) reduced; fronds
typically unroll from base forming a fiddlehead.
K: Plantae Div: Filicophyta
(Div: Pterophyta)
4. Homosporous (mostly); Sporangia (2n) are clustered in groups
(called sori) on the backsides of fronds or onto special modified leaves
(called fertile stems).
K: Plantae Div: Filicophyta
(Div: Pterophyta)
5. Two major types of sporangia in ferns:
* Eusporangiate - sporangia sessile or on massive stalks on
fertile spikes. Many spores (n) produced.
* Leptosporangiate - sprorangia on delicate stalks. Small but
definite number of spores produced.
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Reproduction:
Eusporangiate & Leptosporaginate
meiosis
sporangium (2n) -------------> spores (n) --> monoecious gametophytes (n)
extine
intine
fertilization
------------------------> zygote (2n) --> young sporophyte (2n)
K: Plantae Div: Filicophyta
(Div: Pterophyta)
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Stem cross-sections:
Adiantum - solenostele
Thelyptris - dictyostele
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Fern sori - Leptosporangiate, Genus: Thelypteris
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Fern sori - Leptosporangiate, Genus: Thelypteris
K: Plantae Div: Filicophyta
(Div: Pterophyta)
* Leptosporangiate - sprorangia on delicate stalks. Small but
definite number of spores produced.
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Fern sori - Leptosporangiate, Genus: Thelypteris
Release of spores: light requirement (red – 500 to 700 nm) in most
species.
Light quality and quantity affects the growth of gametophytes. Most spores
will not germinate in the darkness.
Some ferns (bracken fern) produce antheridogen (by prothalli) causes
young prothalli to produce antheridia only  sperm. Promotes Crossfertilization.
Antheridogen causes spore producion in some ferns – even in the dark.
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Fern sori - Leptosporangiate, Genus: Thelypteris
development of embryo --> sporophyte:
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Ceratopteris
C-Fern
K: Plantae Div: Filicophyta
(Div: Pterophyta)
Some leptosporangiate ferns:
common
1. Regular Alternation of Generations
Rare
2. Apogamy - gametophyte (n) -----> sporophyte (n)
(no fusion of gametes)
3. Apospory - sporophyte (2n) -----> gametophyte (2n)
(without spore production - produces dipolid
gametes 2n that may form polyploid - 3n, 4n off-spring after fertilization)
* Chromosome no. alone does not explain differences in forms.
K: Plantae Div: Filicophyta
(Div: Pterophyta)
A small number of leptosporangiate ferns are heterosporous:
Class: Filicopsida Order: Marsileales Genus: Marselia aquatic
K: Plantae Div: Filicophyta
(Div: Pterophyta)
A small number of leptosporangiate ferns are heterosporous:
Class: Filicopsida Order: Marsileales Genus: Marselia aquatic
mega and microsporangia inside of sporocarps on
short lateral branches.
K: Plantae Div: Filicophyta
(Div: Pterophyta)
A small number of leptosporangiate ferns are heterosporous:
Class: Filicopsida Order: Marsileales Genus: Marselia
aquatic
K: Plantae Div: Filicophyta
(Div: Pterophyta)
A small number of leptosporangiate ferns are heterosporous:
Class: Filicopsida Order: Marsileales Genus: Marselia
aquatic
K: Plantae Div: Filicophyta
(Div: Pterophyta)
“Evolution of “Plants”