Term
Protista
Algae, Protozoa, and Slime Molds |
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Definition
•Include simple eukaryotes and multicellular
•Most are microscopic, but some multi-cellular organisms can reach 60 meters.
•Diverse lifestyles: Photosynthetic, predatory and parasitic.
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Term
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Definition
•Photosynthetic •Major groups are distinguished by their energy storage products, cell walls and color •Also distinguished by cellular organization: unicellular, filamentous, colonial, or multicellular |
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Term
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Definition
•Six major clades: 1)Chlorophyta – green algae 2)Phaeophyta – brown algae 3)Rhodophyta – red algae 4)Bacillariophyta – diatoms 5)Pyrrhophyta – dinoflagellates 6)Euglenophyta - euglenoids |
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Term
Algae Clade Chlorophyta (Green Algae) |
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Definition
•Considered to be ancestral to land plants –Chlorophyll a –Chlorophyll b –Starch as carbohydrate storage –Cells walls of cellulose –Unicellular, filamentous, or colonial |
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Term
Algae Unicellular Green Algae |
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Definition
Unicellular Green Algae •Chlamydomas –Motile, found in soil, lakes, ditches –Highly adaptable, live in many different environments throughout the world. –Usually reproduce asexually, but will undergo sexual reproduction in response to poor environmental conditions. |
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Term
Algae Filamentous Green Algae |
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Definition
•Spirogyra –Running streams; secrete mucilage which makes them feel slippery –Asexual reproduction is by fragmentation only. The strands grow until they break, thus forming more individuals. Again, takes place during favorable conditions –Sexual reproduction occurs via a process known as conjugation. (using conjugation tubes) |
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Term
Algae Filamentous Green Algae |
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Definition
•Cladophora –Exists in haploid and diploid forms –Diploid stage produces spores – sporophyte –Haploid stage produces gametes – gametophyte –Alternation of generations |
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Term
Algae Colonial Green Algae |
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Definition
•Volvox –Consists of many Chlamydomonas-like cells bound in a common spherical matrix. –Each cell in the sphere has two flagella –One of the most structurally advanced colonial forms of algae – |
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Term
Algae Clade Phaeophyta (Brown Algae) |
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Definition
•Primarily marine •Usually grow in cool water •Brown pigment–fucoxanthin •Range in size from microscopic to kelps over 100 m long •Economically important: i.e. Laminaria is marketed as the edible kombu |
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Term
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Definition
•Complex reproductive organs (Conceptacles) –Oogonia- multicellular organs that produces eggs –Antheridia- multicellular organs that produce sperm •Harvested for iodine, potassium, alginates (soup thickeners, ice cream), fertilizer |
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Term
Algae Rhodophyta (Red Algae) |
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Definition
•Live in warm marine waters •Their colour is due to the red pigment phycobilin, masking the green color of chlorophyll. This red pigment is very well suited to absorb the green and blue-green light in somewhat deeper sea water •Agar is made from red algae |
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Term
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Definition
•Diatoms are single celled algae that have two hard coverings of silica, SiO2 •The two sides are called the epitheca and hypotheca; they fit together like a box and lid or petri dish, the epitheca overlapping the hypotheca. |
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Term
Algae Bacillariophyta (Diatoms) |
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Definition
•Diatoms are extremely abundant in both freshwater and marine ecosystems •It is estimated that 20% to 25% of all organic carbon fixation on the planet (transformation of carbon dioxide and water into sugars, using light energy) is carried out by diatoms. This is possible because they contain chlorophyll Diatoms are thus a major food resource for marine and freshwater microorganisms and animal larvae, and are a major source of atmospheric oxygen. |
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