Liverworts

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Liverworts

• Domain Eukarya
• Kingdom Plantae
• Phylum Bryophyta

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Looking Back at Bio 115

• The Organism as a Unit of Life

Cellular Structure (cell unit of life)one or
many! Metabolism Homeostasis (PSN, Resp, N2fix,
ferment, etc.) Growth irreversible change in
size Reproductionfailure extinction Acclimatiza
tion-short term responses behavior Adaptation-lo
ng term responses evolution
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Shifting Kingdoms
Lumpers
Splitters
Plantae
2 3 5 6 8
Bacteria Bacteria Bacteria Bacteria Bacteria
Archaebacteria Archaebacteria Archaebacteria Archaebacteria Archaebacteria
Archezoans Archezoans Archezoans Archezoans Archezoans
Euglenoids Euglenoids Euglenoids Euglenoids Euglenoids
Chrysophytes Chrysophytes Chrysophytes Chrysophytes Chrysophytes
Green Algae Green Algae Green Algae Green Algae Green Algae
Brown Algae Brown Algae Brown Algae Brown Algae Brown Algae
Red algae Red algae Red algae Red algae Red algae
Slime Molds Slime Molds Slime Molds Slime Molds Slime Molds
True Fungi True Fungi True Fungi True Fungi True Fungi
Bryophytes Bryophytes Bryophytes Bryophytes Bryophytes
Tracheophytes Tracheophytes Tracheophytes Tracheophytes Tracheophytes
Protozoans Protozoans Protozoans Protozoans Protozoans
Myxozoans Myxozoans Myxozoans Myxozoans Myxozoans
Multicellular Animals Multicellular Animals Multicellular Animals Multicellular Animals Multicellular Animals
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How Many Kingdoms?
Extant
Extinct
Long Time with Prokaryotes only
Original Cell
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Bryophytes

• Although they have no true xylem or phloem and do
  reproduce sexually with spores.
• Never any doubt about their status as plants
• Cellulose walls glued together with pectin
• Chlorophyll a and b, xanthophylls, carotenoids
• Store starch
• Standard plant chloroplasts, mitochondria, golgi,
  etc.
• Diplohaplontic (sporic) life history
• Oogamous gametes
• Do have conductive tissue hydroids and leptoids
• 500 species
• Two Major Classes
• Hepaticopsida (liverworts)
• Musci (mosses)

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Haploid (1N) gametophyte thallus has
photosynthetic chambers with chimney cells for
gas exchange. The thallus grows in notches at
thallus ends. In some seasons produce gemmae cups
(cupules) that contain tiny gemmae for asexual
reproduction of gametophyte. Beneath thallus,
uniseriate rhizoids anchor to substrate.
Marchantia polymorpha Thallose liverwort
http//www.boga.ruhr-uni-bochum.de/html/Marchantia
.polymorpha.ja1.jpg
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http//www.hiddenforest.co.nz/bryophytes/liverwort
s/thallose/marchantiaceae/images/march01ma.jpg
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Generalized Sporic (diplohaplontic) Life Cycle
In the gametic (diplontic) shortcut the product
of meiosis becomes a gamete (no multicellular
haploid)
In the zygotic (haplontic) shortcut, the zygote
undergoes meiosis (no multicellular diploid)
SYNGAMY
gametes
zygote
germination
mitosis
gametangia
mitosis
differentiation
differentiation
1N
2N
Sporophyte
Gametophyte
differentiation
differentiation
sporangium
mitosis
mitosis
germination
sporocyte
spores
MEIOSIS
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Generalized Sporic (diplohaplontic) Life Cycle
SYNGAMY
gametes
zygote
germination
mitosis
gametangia
mitosis
differentiation
differentiation
1N
2N
Sporophyte
Gametophyte
differentiation
differentiation
sporangium
mitosis
mitosis
germination
sporocyte
spores
MEIOSIS