Algae Flashcards
what are algae?
photosynthetic protists.
Phycology is the study of what?
algae.
In the oceanic setting, what do algae do?
they play a similar role for photosynthetic land plants.
What is a monophyletic group?
an ancestor and all its descendants.
What is a paraphyletic group?
an ancestor and only some of its descendants. (superficial.)
What is a polyphyletic group?
unrelated organisms grouped together.
What three characteristics are used to determine differences between green, red and brown algae?
- chloroplast pigments.
- food storage form.
- cell wall.
Brown (Phaeophyta) Algae have what chloroplast pigments?
Chl a, Chl c, and carotenoids. The predominant is fucoxanthin.
Red (Rhodophyta) Algae have what chloroplast pigments?
Chl a and phycobilin. The predominant is phycoerythium. (erithro means red.)
Green (Chlorophyta) Algae have what chloroplast pigments?
Chl a, Chl b, and carotenoids. The predominant is Chl a.
What food storage form do Phaeophyta use (brown)?
Laminarin (Stored in vacuoles) makes up 34% of body weight.
What food storage form do Rhodophyta (red) use?
Fioridean starch (cytosol.)
What food storage form do green (Chlorophyta) use?
starch in plastids.
What is the cell wall of Phaeophyta (Brown) made of?
cellulose and algin.
What is the cell wall of Rhodophyta (red) made of?
cellulose, carrageenan, and agor.
What is the cell wall of Chlorophyta (green) made of?
cellulose, hemicellulose, and pectin.
What is algin?
gooey stuff that keeps the cell hydrated.
What are the characteristics of Division Phaeophyta?
- mostly marine
- multicellular
- dominate rocky shorelines in cold water.
- Have two growth forms: rockweed and kelp.
What are the characteristics of rockweed?
- short and highly branched.
- gametic meiosis.
- only haploid at gametes.
What are the characteristics of kelp?
- taller, fewer branches.
- have alteration of generations life cycle
- multicellular diploid stage
- reproduction occurs in the haploid stage.
What are the parts (anatomical) of the kelp plant?
- the holdfast (looks like a root but not a root)
- the stipe (looks like a stem)
- blade (looks like a leaf, is photosynthetic and has similar cells.)
- air bladders buoyancy.
How large can giant kelp grow?
greater than 60 meters.
In the deeper parts of the ocean, how do kelp transport food?
with trumpet cells. (look like phloem.)
Why do kelp not need a xylem like organ?
they are already surrounded by water.
What are some ways we use brown algae?
kelp is burned for ash. are used as fertilizer, and algin is used in foods, paper, textiles, brewing, etc.)
What are the characteristics of the division Rhodophyta? (red)
- mostly marine, especially tropical or warm waters.
- most are multicellular.
- found more deep in water than any other photosynthetic organism. (268 m in depth, deepest organism found; 100 m shallower if not red algae.)
- can be purple, blue, or black.
- biggest group deposits lime in cell walls. (coralline algae, but are not corals.)
What are the uses of red algae?
- eaten for food (Irish moss was eaten during potato famine.)
- source of agar.
- source of carrageenan (emulsifier)
What are the characteristics of Division Chlorophyta?
- more diverse than brown or red.
- occur in fresh/salt water, trees, soil, and snow.
- often recognized by cell division (one chloroplast per cell.)
- alternation of generations (isomorphic)
viridaplantae is a monophyletic group that contains what two organisms?
green algae and plants.
Green Algae is what type of phyletic group?
paraphyletic.
Classes end in what?
phycae.
What are the characteristics of Plantae?
alteration of germinations life cycle and both haploid and diploid multi-cellular stages.
What are the uses of green algae?
base of most aquatic food chains, some are eaten, used by animals to become photosynthetic (Kleptoplasty).
Chlorophyta includes what type of algae groups?
unicellular, filamentous, colonial, coenocytic (multi-nuclear) and multicellular.
