Green Algae Flashcards
Green algae are the most diverse group of algae, and share a common ancestor with ___
land plants
are green algae single or multicellular
Single celled to multicellular
where does green algae live
Diverse habitats – snow, desert, lichens, trees, sponges..
what monophyletic group does green algae live in
Viridiplantae is a monophyletic group that includes green algae and land plants
Synapomorphies shared with land plants
chlorophylls a and b, store starch inside plastids,
cellulosic cell walls, similar flagellated sperm cells
Chlorophytes are mainly ___ species; can be ___ (cells), and include
freshwater, unicellular or colonial, Chlamydomonas and volvox
Chlamydomonas is a ___ model organism
Chlamydomonas is a unicellular model organism
Chlamydomonas life cycle, What is the dominant phase of the life cycle?
What type of meiosis?
n dominant, isogamous (or asexual), no alternation of generations, zygotic meiosis
Volvox is a spheroid colony that can reproduce ___
sexually or asexually
features of volvox
Hundreds to thousands of vegetative photosynthetic cells on the outside
* Left colony – reproducing asexually – mitosis has produced 16 juvenile colonies
* Right colony – reproducing sexually – colonies produce eggs and sperm
* Cells are ‘stuck together’ with elaborate extracellular matrix of glycoproteins (not pectin yet!)
The Ulvophytes are mainly ___ species that are ____ or composed of flat ___ of cells
marine, filamentous, sheets
ulva reproduction
2n + n dominant, isogamous and anisogamous, isomorphic, sporic meiosis
Charophyte algae includes members that most closely resemble ___
land plants
Evidence that Charophyte algae includes members that most closely resemble land plants
Asymmetrical flagellated cells with distinct multilayered structures
* Nuclear envelope breaks down during mitosis
* Oogamous
* Phragmoplasts at cytokinesis
* Many biochemical molecules(phytochrome, flavonoids, pectin, etc)
Pectin?
Phragmoplast
An important taxonomic character that is similar to the
sperm of bryophytes and some vascular plants
___ is a filamentous Charophyte example
Spirogyra
Spirogyra sexual reproduction: ___ reproduction involves formation of ___ tubes between ___ cells (neither are flagellated), followed by ___ meiosis
Sexual reproduction involves formation of conjugation tubes between isogamous cells (neither are flagellated), followed by zygotic meiosis
Zygospore is surrounded by ___ – the most ___ biopolymer known!
sporopollenin, resistant
Coleochaete and Chara were long thought to be the
closest relatives of land plants; both are ___
oogamous
Oogonium produces
eggs
antheridium produces
sperm
chara life cycle
ploidy
[]gamous
AOG?
zygote details
n dominant, oogamous, no alternation of generations, Zygote is retained and nourished by the parent! Enclosed in sporopollenin!
It is becoming more accepted that the ___ are actually more closely related to land plants!
Zygnematophyceae
Recent work with Penium margaritaceum suggests that the closest ancestor to land plants had ____
simpler body plans
