Correction: perigynous - University of...
Transcript of Correction: perigynous - University of...
Ovary position
Correction: perigynous
Major Groups of Plants &
Life Cycles
Green plants (Kindgom Plantae)
“Green algae”
Green plants
Live
rwor
ts M
osse
s H
ornw
orts
Lyco
phyt
es
Fern
s
Gymnosperms Angiosperms Seed plants
Tracheophytes (vascular plants) Bryophytes
Embryophytes (land plants)
Phylogeny of Green Plants
Embryophytes (land plants)
“Green algae” Green plants
Embryo
http://www.vcbio.science.ru.nl/
Sporopollenin
http://en.wikivisual.com/
Cuticle
http://www.uni-muenster.de/GeoPalaeontologie/Palaeo/Palbot/cut1a.jpg
http://www.botany.wisc.edu/courses/botany_330/
Pop Quiz
According to the phylogenetic tree shown in the previous slide, the group “green algae” is:
A. Monophyletic B. Paraphyletic C. Polyphyletic D. I have no idea
Phylogeny of Green Plants
Embryophytes (land plants)
“Green algae” Green plants
http://www.botany.wisc.edu/courses/botany_330/
Embryo
http://www.vcbio.science.ru.nl/
Sporopollenin
http://en.wikivisual.com/
Cuticle
http://www.uni-muenster.de/GeoPalaeontologie/Palaeo/Palbot/cut1a.jpg
http://ux.brookdalecc.edu/fac/biology/lab/102/images/liverwort1.jpg http://www.hiddenforest.co.nz/bryophytes/mosses/familys/racopilaceae/images/racop01bt.jpg http://www.cartage.org.lb/en/themes/Sciences/BotanicalSciences/ClassificationPlants/Cryptogamia/Bryophyta/Nonvascular/hornwort1.JPG
Tracheophytes (vascular plants)
“Bryophytes”
Phylogeny of Land Plants
Embryophytes (land plants)
stomata
tracheids
http://www.freewebs.com/jdingfel/Stomata.jpg
http://f030091.ffpri.affrc.go.jp/image/OM_code_E/60.Tracheids.gif
Phylogeny of Tracheophytes
Tracheophytes (vascular plants)
Seed plants (Gymnosperms+Angiosperms)
true leaves
seeds
pollen
Textbook DVD WSJ
Textbook DVD WSJ
http://home.pacbell.net/kenww/my_iris/other/I_foetidissima_seeds-web.jpg
http://www.bioquest.org/scope/projectfiles/PollenMixb.jpg
Phylogeny of Seed Plants
Angiosperms
Seed plants
Gymnosperms
reduced female gametophyte
endosperm flowers
carpel
bitegmic ovules Textbook DVD WSJ
http://www.dickcontino.com/images/ginkgo.jpg http://www.emc.maricopa.edu/faculty/farabee/BIOBK/fertil1.gif
http://web.gccaz.edu/~lsola/Flower/capsella3.jpg
Summarize the synapomorphies for major groups of land plants
“Green algae”
Green plants
Live
rwor
ts M
osse
s H
ornw
orts
Lyco
phyt
es
Fern
s
Gymnosperms Angiosperms Seed plants
Tracheophytes (vascular plants) Bryophytes
Embryophytes (land plants)
Generalized Life Cycle in Plants
Alternation of generations = cycle between haploid (1n) and diploid (2n) phase.
http://en.wikipedia.org/wiki/Alternation_of_generations
Generalized Life Cycle in Plants vs. Animals
What’s the difference between plants and animals?
Some key terms in the plant life cycle
Meiosis = reductive nuclear division process that reduces the chromosome number of a cell by half (from a diploid cell to 4 haploid daughter cells).
Mitosis = nuclear division that maintains the parental chromosome number for daughter cells; the basis for growth in size and asexual reproduction in plants.
Fertilization = fusion of the sperm nucleus and the egg nucleus to form a zygote.
Zygote (2n) = the cell formed by fusion of the gametes (sperm [1n] and egg [1n]) at fertilization; embryo.
Spore (1n) = the first cell of the gametophyte generation; product of meiosis.
Sporophyte (2n) = diploid, spore-producing generation of the plant life cycle, that produces structures called sporangia (singular, sporangium).
Gametophyte (1n) = haploid, gamete-producing generation of the plant life cycle, that produces structures/sex organs—gametangia (male: antheridium, produce sperm; female: archegonium, produce eggs).
Life cycle: bryophytes
http://8e.devbio.com/image.php?id=523
Life Cycle: ferns and fern allies
http://8e.devbio.com/image.php?id=524
Life Cycle: angiosperms (flowering plants)
http://8e.devbio.com/image.php?id=525
embryo vs. embryo sac
Embryo (2n): young sporophyte, from the first cell after fertilization until germination of the seed (in seed plants) or emergence from protective gametophytic tissues (other land plants); zygote.
Embryo sac (1n): female gametophyte of the angiosperms (flowering plants).
Some key terms in the angiosperm life cycle
Seed plants (angiosperms and gymnosperms) – Sporophyte dominant. Gametophyte dependent on sporophyte and very reduced and short-lived.
Microsporangia in pollen-bearing structures that produce male gametophytes; in pollen cones (gymnosperms) or anthers (angiosperms). Male gametophytes = short-lived and inside the pollen grain; 2-3-celled, 1 cell becomes sperm.
Megasporangia in ovules that produce female gametophytes, which produce eggs; in cones (gymnosperms) or ovaries (angiosperms).
Spores grow into small gametophytes which are contained within the parent plant (inside cones or flower).
Some key terms in the seed plant life cycle
Which comes first: pollination or fertilization?
Pollination = transfer of pollen from anther to stigma.
Fertilization = fusion of sperm nucleus and egg nucleus.
Pollination occurs only in seed plants! Fertilization occurs in all sexually reproducing organisms.
In seed plants, pollination must occur before fertilization!