Card Set Information

2010-04-18 17:53:25

ch 20&22
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  1. Protist
  2. o Include any eukaryote not a plant, animal, or fungus
    • o Mostly single-celled
    • o Approximately 60,000 species
  3. Protists
  4. o Include any eukaryote not a plant, animal, or fungus
    • o Mostly single-celled
    • o Approximately 60,000 species
  5. autotrophs
    Photosynthetic protists are collectively known as algae

    Ingest food with pseudopod
  6. heterotrophs
    Absorb nutrients from surroundings

    Single-celled, non-photosynthetic protists are collectively known as protozoa
  7. Reproduction
  8. o Reproduce asexually by mitosis
    • o Some also reproduce sexually
    • o Occurs during certain time of year or circumstances (e.g. a crowded environment or a food shortage)
  9. The Excovates
  10. o Lack mitochondria
    • o 2 major groups
    • - Diplomonads: have two nuclei and move about by means of multiple flagella
    • - Parabasalids: live inside animals
    • o Diplomonads
    • -Giardia: a parasitic diplomonad
    • -Acquired by hikers who drink from infected streams, diarrhea and nausea
    • -Cyst phase released in animal feces
    • +develop into adult form after ingestion
  11. The Euglenozoans
  12. o Have distinctive mitochondria
    • o 2 major groups
    •  Euglenids
    •  Kinetoplastids
  13. Euglenids
  14.  Single-celled, fresh-water protists
    •  Best known example is Euglena
    •  Moves by whipping single flagellum
    •  Photosynthetic
  15. Kinetoplastids
  16.  All species have one or more flagella
    •  Can be used for propulsion or food gathering
    •  Trypanosomes infect the blood causing African sleeping sickness
  17. The Stramenophiles
  18. o Have fine, hair-like projections on flagella
    • o Some are photosynthetic
    • o Major stramenophile groups
    •  Water molds
    •  Diatoms
    •  Brown algae
  19. Water Molds
  20.  Also known as oomycetes
    •  Long filaments aggregated into cottony tufts
    •  Many are soil and water-based decomposers
  21. Diatoms
  22.  Found in both fresh and salt water
    •  Part of floating phytoplankton community
    •  Perform 70% of all photosynthesis
    •  Produce shells of silica
  23. Brown Algae
  24.  Form multicellular aggregates (seaweeds)
    •  Not closely related to plants
    •  Contain brownish-yellow and green (chlorophyll) pigments
  25. The Alveolates
  26. o Single-celled with small cavities beneath cell surface (alveoli)
    • o Photosynthetic, parasitic, and predatory
    • o Major alveolate groups
    •  Dinoflagellates
    •  Apicomplexans
    •  Ciliates
  27. Dinoflagellates
  28.  Mostly photosynthetic
    •  2 whip-like flagella
    •  Most species live in salt water
    •  Nutrient-rich water causes population explosion called "red tides"
  29. Apicomplexans
  30.  Parasitic
    •  Form infectious spores
    •  Spores transmitted between hosts by food, water, or insect bites
  31. Ciliates
  32.  Inhabits both fresh and salt water
    •  Highly complex unicellular organization
    •  Paramecium has vacuoles and cilia
  33. The Cercozoans
  34. o Have thin, threadlike psuedopods, which extend through hard shells in some species
    • o Cercozoans include
    •  Foraminifera
    •  Radiolarians
  35. The Amoebozoans
  36. o Amoebozoans move by extending pseudopods, also used for feeding
    • o Aquatic and terrestrial environments
    • o Generally do not have shells
    • o Major groups of amoebozoans
    •  Amoebas
    •  Slime molds
  37. Amoebas
  38.  Found in freshwater lakes and ponds
    •  Predators that stalk and engulf prey
    •  One species causes amoebic dysentery
  39. Slime Molds
  40.  Distinctly unique lineage among protists
     Physical form blurs distinction between a colony versus an individual
  41. The Red Algae
  42. o Multicellular, photosynthetic seaweeds
    • o Pigments combined with chlorophyll produce bright red to black appearances
    • o Found exclusively in marine environments
  43. The Green Algae
  44. o Photosynthetic
    • o Both multicellular and unicellular species
    • o Found in both freshwater and marine environments
    • o Some form colonies of clustered cells (e.g. Volvox)
    • o Mostly microscopic forms but Ulva (sea lettuce) is a multicellular leaf-sized green algal seaweed
    • o Green algae are closely related to plants
    • o Early plants may have been similar to today’s multicellular green algae
  45. Fungi
  46. o Most fungi are multicellular
    • o Cells are surrounded by cell walls composed of chitin, a nitrogen-containing polysaccharide
    • o Approximately 60,000 species
  47. Fungal Body Structure
  48. o Body of almost all fungi is a mycelium, an interwoven mass of threadlike filaments called hyphae (singular, hypha)
    • o Fungal Body Structure
    • o Hyphae of most species are divided into many cells by partitions called septa (singular, septum); each cell possesses one or more nuclei
  49. Nutrition and Fungal Lifestyles
  50. o All are heterotrophic
    • o Secrete enzymes outside their bodies and absorb the digested nutrients
    • o Decomposers (saprobes) feed on dead organic material and wastes
    • o Parasites absorb nutrients from cells of living hosts
    • o Symbiotic fungi live in mutually beneficial relationships
  51. Fungal Reproduction
  52. o Both asexual and sexual reproduction involve the production of spores within fruiting bodies
    • o Reproduction
    •  Asexual occurs under stable conditions
    •  Fragmentation of the mycelium
    •  Asexual spore formation by mitosis
    •  Sexual occurs under unstable conditions
    •  Hyphae of different fungi fuse
    •  Haploid nuclei fuse to form a diploid zygote
    •  Zygote undergoes meiosis to form haploid sexual spores
  53. Classification of Fungi
  54. o Classified based upon spore production
    •  Chytridiomycota (chytrids)
    •  Zygomycota (zygote fungi)
    •  Ascomycota (sac fungi)
    •  Basidiomycota (club fungi)
  55. The Chytrids
  56. o Mostly aquatic
    • o Reproduce both asexually and sexually
    • o Form flagellated spores that require water for dispersal
    • o Feed on dead aquatic material
    • o Some species are parasites of plants and animals
    •  One species believed to be a major cause of the worldwide die-off of frogs
    • o Primitive chytrids are believed to have given rise to the other groups of modern fungi
  57. Zygomycetes
  58. o Most live in soil or on decaying plant or animal material
    • o Reproduce both asexually and sexually
    • o Sexual spores are thick-walled zygospores
    • o Asexual reproduction:
    •  Haploid spores are produced via mitosis in black spore cases called sporangia
    • o Sexual reproduction
    •  Nuclei fuse to form a diploid zygospore
    • o Rhizopus, the black bread mold
  59. Ascomycetes
  60. o Live in a variety of marine, freshwater, and terrestrial habitats
    • o Reproduce both asexually and sexually
    • o Sexual spores form in saclike asci
    • o Better known examples include
    •  Most of the food-spoiling molds, Morels and truffles (edible delicacies), Penicillium, the mold that produces penicillin (the first antibiotic), Yeasts (single-celled fungi)
    • o During asexual reproduction
    •  Haploid spores are produced via mitosis at the tips of specialized hyphae
    • o During sexual reproduction
    •  Each fruiting body contains numerous saclike cases called asci (singular, ascus)
  61. Basidiomycetes
    • o Live in a variety of marine, freshwater, and terrestrial habitats
    • o Usually reproduce sexually
    • o Sexual spores form in club-shaped basidia
    • o Better known examples include
    •  Mushrooms (some are edible, others are poisonous), Puffballs, Shelf fungi (decomposers of wood), Stinkhorns, Rusts and smuts (plant parasites), Yeasts

    • During sexual reproduction:
    • o Each fruiting body contains club-shaped structures called basidia (singular, basidium
  62. Symbiotic Relationships
  63. o Lichens are symbiotic associations between fungi (usually an ascomycete) and algae or cyanobacteria
    •  Fungus provides photosynthetic partner with shelter and protection
    •  Photosynthetic partner provides fungus with food (sugar)
    • o Mycorrhizae (singular, mycorrhiza) are symbiotic associations between fungi and plant roots
    •  Fungus provides plant with water, minerals, and organic nutrients it absorbs from the soil
    •  Plant provides fungus with food (sugar)