pteridophyte reproduction - christian brothers...

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Pteridophyte reproduction

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Modified 17-13 (19-9) Embryophytes

“Bryophytes”

Rhy

nia

(Fos

sil)

Lyco

podi

ophy

ta

Pteridophyta

Transition to land

megaphylls

microphylls

Microphylls• One vascular trace

– No branching vasculature in leaf– Forms from protostele

http://28.media.tumblr.com/tumblr_lgpco8M9Ie1qa2aauo1_500.jpg

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Megaphylls– Branching vascular traces (veins) in leaves– Typically large

http://intro.bio.umb.edu/111-112/OLLM/112s99/phyla/plants/pterophyta.jpg

Are not always large.

Highly reduced megaphylls in Equisetales.

http://www.missouriplants.com/Ferns/Equisetum_hymenale_stems.jpg

Remember the STELES

Pteridophyta

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Stele modification in Pteridophyta

(a few with eustele)

ancestor had protostele,like Lycopodiophyta.

siphonostele

eustele

Protosteles

Lycopodiophyta

Siphonosteles

Most ferns, though, have siphonosteles with leaf gaps

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Eusteles

Equisetales—eusteles; convergent with seed plants.

Heterosporous ferns

Eusporangiate ferns

Equisetales

Modification of life cycle and reproduction in Pteridophyta

heterosporyendosporic gametophyte

Filicales

Equisetales

ancestor had dominant homosporoussporophyte with undergroundnon-photosynthetic gametophyte,like Lycopodiaceae

above-ground photosyntheticgametophyte

leptosporangia


Life cycles: above-ground photosynthetic gametophyte

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Heterosporous ferns

Equisetales

Eusporangiate ferns

Modification of life cycle and reproduction in Pteridophyta2. Leptosporangia


Filicales

Eusporangiate ferns



leptosporangia

Life cycles: eusporangia vs. leptosporangia

Eusporangia: large1 to 1000’s of spores the basal (primitive) conditionwalls several cells thick found in most land plants

Leptosporangia: small64 spores

walls one cell thickhave annulus (thickened ring) grouped into sori (sing. sorus)only in Filicales and heterosporous ferns

Life cycles: eusporangia

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Life cycles: eusporangia in a eusporangiate fern (Botrychium)

Life cycles: leptosporangia

Life cycles: leptosporangia in Filicales

http://www.google.com/imgres?q=leptosporangia+in+filicales&hl=en&client=firefox-a&hs=HLb&sa=X&rls=org.mozilla:en-US:official&biw=748&bih=393&tbm=isch&prmd=imvns&tbnid=cDA5fNilc4DjaM:&imgrefurl=http://www.increasemyvocabulary.com/definition/of/leptosporangium/&docid=UL-NACsnDhf5jM&imgurl=http://farm3.static.flickr.com/2127/2263445746_61832fff71.jpg&w=500&h=375&ei=-2OsTtbwC62rsALHi8WADw&zoom=1

http://t0.gstatic.com/images?q=tbn:ANd9GcQ5dCnB8I61yQSkLGFZHRNK9szAhC4CieR19Yvgi78YQTs01RUurg

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Life cycles: leptosporangia grouped into sori in Filicales(Thelypteris)

http://t2.gstatic.com/images?q=tbn:ANd9GcR67ZaOrG_IZnVCTJlKNnzNb9xRzv2WRyzTn65QY9_qNAtdmw-d

Life cycles: leptosporangia grouped into soriin Filicales (Asplenium)

http://t2.gstatic.com/images?q=tbn:ANd9GcRa-R-awiaCHFAk1U2wWgyE4uwVRf-2z5DuiTDyJ5trjRpP7kMP

Heterosporous ferns

Equisetales

Eusporangiate ferns

Modification of life cycle and reproduction in Pteridophyta3. Heterospory and endosporic gametophytes


Filicales

Eusporangiate ferns



leptosporangia

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Life cycles: heterospory

The life cycle of Selaginella is the same as that found in theheterosporous ferns and in the seed plants.

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Embryophytes

“Bryophytes”

Rhy

nia

(Fos

sil)

Lyco

podi

ophy

ta

Pteridophytes

Transition to land

megaphylls

Equisetales: brief overview

--highly reduced megaphylls--eusteles--homosporous

i--eusporangia--above-ground photosynthetic gametophyte--strobili--hollow, jointed stems embedded with silica--one genus, Equisetum, about 15 species;

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Equisetales: Equisetum

Equisetales is the only fern group with strobili.Strobili are stems withmodified leaves–sporophylls—clustered on

http://www.sbs.utexas.edu/bio406d/images/pics/equ/Equisetum%20hyemale%20strob1.jpg

p p ythem. These sporophylls are often called sporangiophoreson Equisetum.

Equisetum: strobili

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Live

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Embryophytes

“Bryophytes”R

hyni

a (F

ossi

l)Ly

copo

diop

hyta

Pteridophytes

Transition to land

megaphylls

Eusporangiate ferns: brief overview

--megaphylls--protosteles--homosporoushomosporous--eusporangia--underground, non-photosynthetic gametophyte--includes Psilotales and Ophioglossales--7 genera, about 70 species

Eusporangiate ferns: Ophioglossales: Botrychium

What you’re seeing here is one leaf

http://www.rook.org/earl/bwca/nature/ferns/botrychium-multifidum-1sm.jpg

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Eusporangiate ferns: Ophioglossales: Ophioglossum

http://hengduan.huh.harvard.edu/fieldnotes/photos/show_image?image_id=1140

Eusporangiate ferns: Psilotales: Psilotum

http://t0.gstatic.com/images?q=tbn:ANd9GcRN0JvXD52gT892P9oJD7fNeMmehdMwcUyqLf8yF_ATVFbdvvh0

Live

rwor

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Embryophytes

“Bryophytes”

Rhy

nia

(Fos

sil)

Lyco

podi

ophy

ta

Pteridophytes

Transition to land

megaphylls

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Heterosporous ferns: brief overview

--all aquatic--megaphylls--siphonosteles--heterosporousp--leptosporangia--endosporic gametophyte--includes Marsileales and Salviniales--5 genera, about 70 species

Heterosporous ferns: Salviniales: Azolla

http://nas.er.usgs.gov/XIMAGESERVERX/2007/20071004180006.jpg

Heterosporous ferns: Salviniales: Salvinia

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Heterosporous ferns: Marsileales: Marsilea

Live

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Embryophytes

“Bryophytes”

Rhy

nia

(Fos

sil)

Lyco

podi

ophy

ta

Pteridophytes

Transition to land

megaphylls

Filicales: brief overview

--megaphylls--siphonosteles (mostly) – few with eusteles--homosporoushomosporous--leptosporangia--above-ground, photosynthetic gametophyte--about 320 genera, 10,500 species

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Filicales: Dennstaedtia

Filicales: Pteridium

http://t2.gstatic.com/images?q=tbn:ANd9GcQSnzinzDmcXng7WDPh3-KaypqI3JJUDSxUWSbyCjSa91eTqQOzcg

pteridophyte reproduction - christian brothers...

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