Aquatic Plants – Green , Red , and Brown Algae
-
Upload
kylynn-davis -
Category
Documents
-
view
50 -
download
2
description
Transcript of Aquatic Plants – Green , Red , and Brown Algae
Aquatic Plants – Green, Red, and Brown Algae
www.onacd.ca
Green Algae
Chlamydomonas Spirogyra Ulva
6000 species
single cells
colonies
long filaments.
Green Algae
Algal bloom Volvox
Caulerpa – an invasive seaweed
aquatic (freshwater or marine) or terrestrial
form symbiotic relationships with fungi to form lichens.
Characteristics of Green Algae• chlorophyll a & b (green
color)
• Some have flagella for movement
• cell walls with cellulose
Characteristics of Green Algae
• Sexual reproduction: go through 2 different life stages using a method called “alternation of generations
• Asexual reproduction: by fission, fragmentation or zoospores (motile spores)
Alternation of GenerationsA life cycle in which there are two distinct life stages
that occur alternately for a species
Stage 1 • Diploid (2N – each cell has two sets of chromosomes)
– Called the sporophyte– Produce gametes (= sex cells = haploid cells) by meiosis
Stage 2• Haploid (1N – each cell has one set of chromosomes)
– Called the gametophyte– Fuse to form a sporophyte (= zygote = diploid cells) by
fertilization
ChlamydomonasCharacteristics• Unicellular• Motile, 2 equal flagella• Occur in stagnant water and
damp soil, fresh water and salt water, even in snow!
• Have a nucleus inside their chloroplast
• Possess two small vacuoles which function to remove waste
• Have a light sensitive, red pigment spot which allows the cells to swim towards light
Chlamydomonas Life CycleTake a good look at the diagram below of the life cycle of Chamydomonas
which is an example of alternation of generations. Note the diploid (2N) and the haploid (1N) stages of its life.
Diploid (2N)
Spirogyra
• Algal cells are joined end to end to form filaments (multicellular)
• Mostly freshwater• Generally free floating• Reproduces asexually by fragmentation and sexually by
conjugation• Does not form gametes,
therefore does not go
through alternation of
generations• Undergo conjugation –
exchange of genetic information
Ulva (sea lettuce)• Multicellular green algae
(looks like a plant)• Lives in marine and
brackish water• Has flat, blade like
leaves called a thallus which is made up of two layers of cells
• Gametes are free-swimming and a zygote is formed in the water
Ulva Life Cycle
Mitosis: 1 cell becoming 2 equal diploid cells
Meiosis: 1 cell becoming 4 haploid cells (gametes)
MITOSIS
Lichens • Can be formed by a
symbiotic relationship between green algae and a fungus
• The fungus provides the algae with water and minerals that it absorbs from whatever it is growing on and protects the algae by retaining water and serving as a larger capture area for minerals and nutrients
• The algal cells uses minerals and water to make food for the fungus and itself
Stained slide
Youtube• http://www.youtube.com/watch?v=OHRPfkCeXHg&feature=related killer algae #1
• http://www.youtube.com/watch?v=gE3d3o1nvt8&feature=related killer algae #2
• http://www.youtube.com/watch?v=hkrWSpNY2B4&feature=PlayList&p=D6BA6B6F9097A4F5&playnext=1&playnext_from=PL&index=11 killer algae #3
• http://www.youtube.com/watch?v=9PMUHQo2qaU&feature=PlayList&p=D6BA6B6F9097A4F5&index=12 killer algae #4
• http://www.youtube.com/watch?v=EsNJKvNhCP8&feature=PlayList&p=D6BA6B6F9097A4F5&index=13 killer algae #5
• http://www.youtube.com/watch?v=b8ugGN9lCu0&feature=related volvox
• http://www.youtube.com/watch?v=NzV_tE75SmA&feature=related chlamydomonas
• http://www.youtube.com/watch?v=LsU6xRvGl8k algae lady on Vancouver Island
• http://www.youtube.com/watch?v=8edk6nGMwMs&feature=PlayList&p=E189ADC6E5940F0F&playnext=1&playnext_from=PL&index=2 elodea cytoplasmic streaming– an aquatic angiosperm not an algae
• http://www.youtube.com/watch?v=F_CRQYw9nvc&feature=PlayList&p=D6BA6B6F9097A4F5&playnext=1&playnext_from=PL&index=1 algae as a biofuel
• http://www.youtube.com/watch?v=1MeIgaRfyD4 algae as biofuel
• http://www.youtube.com/watch?v=YO3Gg3YfJ84&feature=related algal blooms are centre stage
Red Algae - Rhodophyta
• Red algae are red because of the presence of the pigment phycoerythrin; this pigment reflects red light and absorbs blue light. Because blue light penetrates water to a greater depth than light of longer wavelengths, these pigments allow red algae to photosynthesize and live at somewhat greater depths than most other "algae".
Importance of red algae
• Nori sushi – high vitamin and protein content – relative simplicity of cultivation, which began in Japan
more than 300 years ago.
• Agar– Bacterial growth medium
• Carrageenan
-food additive/thickener
Importance of red algae
• important in the formation of tropical reefs, – in some Pacific atolls, red algae have
contributed far more to reef structure than other organisms, even more than corals.
– called coralline algae, because they secrete a hard shell of carbonate around themselves, in much the same way that corals do.
• Nori – red algae used for food/sushi
• Agar agar – red algae used for food and bacterial cultures
• Carrageenan – red algae used as a food additive and thickener
• Coralline algae
Brown algae - phaeophyta
• May reach over 30 meters in length.
• Almost all are marine.
• Pigments– chlorophyll c and fucoxanthin.
Brown algae - phaeophyta
• Blades (analogous to leaves) • branch from the stipe, or stalk
• Receptacles– form on the surface of the blades– structures in which the gametes are produced.
• Sargassum – brown algae– Pelagic (free-floating)
• Fucus – also called rockweed– Attached to
rocks via stipes
Youtube
• http://www.youtube.com/watch?v=jcWYAnmm-QE&feature=related kelp forest
• http://www.youtube.com/watch?v=v_aSl3iL7rM cousteau kelp forest
5 Really Bad Algae Jokes…..
Why did the algae and the fungus get married? They took a lichen to each other.
Why do many algae couples drift apart?They prefer planktonic relationships.
Why couldn't the algae keep a girlfriend?He wasn't a fungi.
Why did the algae get pulled over on his way to the pond?He was chloro-plastered.
Why did the algae fail math?He divided when multiplying.He didn’t know algae-bra.