Ch28 Protists

  1. What are the common characteristics of Protists?
    • Most abundant in moist habitats
    • Most are microscopic in sizes
  2. What are three major groups of Protist?
    • Algae- generally photoautotrophic
    • Protozoa- heterotrophic
    • Fungus-Like - resemble fungi in body form and absorptive nutrition
    • IE: Convergent evolution
  3. What is Plankton?
    Swimming or floating

    • Phytoplankton-photosynthetic
    • Protozoan plankton - hetertrophic

    Occur as single cells, colonies or short filaments.
  4. What is Periphyton?
    • Attached by mucilage to underwear surfaces
    • Produce multicellular bodies
    • Seaweeds or Macroalgae
  5. Classified by motility:
    a) Swim
    b) Cilia
    c) Amoeboid Movement
    d) Gliding
    • a) using eukaryotic
    • b) shorter and more abundant than flagella (ie: Ciliates)
    • c) using pseudopodia (ie: Amoebae)
    • d) on protein or carbohydrate slime
  6. Supergrp Excavata

    Trichomonas vaginalis
    Giardia lamblia
    • *Name for feeding groove "excavated" into the cells of many respresentatives
    • *Food particles are taken into cells by phagotrophy (Endocytosis and evolutionary basis for endosymbiosis)
    • * thought to lack mitochandria; but do possess highly modified mitochandria
  7. Supergrp Excavata

    • Interlocking protein strips beneath PM
    • * can crawl through mud
    • Some hetertophic

  8. Supergrp Excavata

    Large mass of DNA (kinoplasts) in single lg mitochondrion

    • Leishmania
    • Trypansosoma brucei
  9. Supergrp of plants and relative:

    Kingdom Plantae:

    Phylum Chlorophyta:
    Phylum Rhodophyta:
    Phylum Haptophyta:
    Phylum Cryptophyta:
    • KP: land plants evolved from green algal ancestors
    • PC: Green Algae
    • PR: Red Algae
    • PH: Dover Cliff
    • PC: Unicellular Flagellates
  10. Green Algae
    • Diverse Structual types
    • Occur in fresh waters, ocean and on land
    • Most r Photosynthetic
    • Cells contains same type of plastids and phosyn pigments as r present in land plants
  11. Red Algae
    • Most r multicellular marine macroalgae
    • Red appearence due to distinctive photosyn
    • Lack flagella
    • Unusually complex life cycle: hv primary plastids derived from cyanobacteria
    • plastids have two envelope membranes
  12. Cryptomonads
    • Unicellular flagellates
    • Contain red, blue-green, or brown plastids
    • Photosynthetic
    • Hv more than 2 envelopes
  13. Haptophytes
    • Primarily unicellular marine photosynizer
    • Hv more than 2 envelopes
    • Known as coccolithophorids covering of white calcium carbonate discs called coccoliths (Dover Cliff)
  14. Supergrp Alveolata

    • C: Ciliates-Conjugation
    • A: Medically impt parasites
    • Plasmodium
    • D: Dinoflagellates -Some photosyn others r not
    • Red tide and mutualistic relationship w coral;

    • Named for saclike membranous vesicle (alveoli)
    • Hv tertiary plastids
  15. Supergrp Stramenopila
    • Wide range of algae, protozoa, and fungus like protists
    • Produce flagellate cells at some point
    • Named for strawlike hairs on the surface of flagella
    • Heterotrophic or photosynthetic
    • Plastids from 2o endosymbiosis w red algae
  16. Supergrp Rhizaria
    Hv thin, hairlike extensions of the cytoplasm called filose pseudopodia

    • Phylum Chlorarachniophyta
    • Phylum Radiolaria
    • Phylum Foraminifera
  17. Supergrp Amoeboza
    • Many types of Amoebae
    • Move using pseudopodia

    Entamoeba Histolytica

    Slime molds
  18. Supergrp Opisthokonta
    Incl. animal and fungal kingdoms and related protists

    Named for single posterior flagellum or swimming cells

    Choanoflagellate Protists
  19. 4 Basic types of Nutrition

    • P: heterotrophs that ingest particles
    • O: heterotrophs that rely on uptake of small organic molecules
    • Photo: photosynthetic
    • M: able to use autotrophy and phagotrophy or osmotrophy depending on conditions
  20. Algal Protists
    • Variety of pigments:
    • Adapt photosystems to capture more lights
    • Water absorbs the longer red and yell wavelengths more than blue and green
    • Accessory pigm absorb light and transfer it to chlorophyll A
    • Varitey of food storage molecules:
    • Starch, polysacchrides and oils
  21. Defense
    • Slimy mucilage or cell walls defend agnst herbivores and pathogens
    • Trichocysts r spear-shaped projectiles to discourage herbivores
    • Bioluminescence- startle herbivores
    • Toxins- inhibit animal physiology (Pfiesteria)
  22. Asexual Reproductions:
    • All Protists can produce asexually
    • Produce cysts with thick, protective walls that dormant in bad conditions
    • Protozoan pathogens spread from one host to other via cysts
  23. Sexual Reproductions:
    • Eukaryotic sexual reprod w gametes and zygotes arose among protists
    • Adaptives bc it produces diverse genotypes
    • Zygotic and sporic life cycles
  24. Zygotic Life Cycle:
    • Unicellular sexually reproducing protists
    • Haploid cells develop into gametes
    • + and - mating strains
    • Thick walled diploid zygotes(Survive like cysts)
  25. Sporic Life Cycle:
    • Multicellular green and brown seaweeds
    • Known as alternation of generations
    • 2 Types multicellular organisms:
    • Haploid gametophyte produces gametes
    • Diploid sporophyte produces spores by meiosis
    • Red Seaweed involves 3 distinct multicellular generations
  26. Gametic Life Cycle:
    • All cells except gametes r diploid
    • Gametes produced by meiosis
    • Diatoms r one of the few protists w this life cycle
  27. Ciliate Sexual Reproduction -Conjugation
    • Most complex sexual process in protists
    • Hv two types of nuclei( single macronucleus and one or more micronuclei)
    • Macronucei r source of info for cell fxn
    • 2 cells pair and fuse - conjugation
    • Micronuclei undergo meiosis, exchange, fusion and mitosis
  28. Parasitic protist life cycle
    • Parasitic protists often use more than one host organism in which different life stages occur
    • Malarial parasite Plasmodium alternate bwn humans and anopheles mosquitos
Card Set
Ch28 Protists
Ch 28