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!