Chapter 22: Protists Flashcards
- Characteristics of Excavates
•Hollow ventral feeding groove •Single cell w/ flagella •Lack Mitochondria -> Adaption to parasitism
1a. Diplomonoadida (double cells)
(double cells)
- two nuclei
- multiple symmetrical flagella
- some free living
- some parasites
1b. Parabasalia (parasitic)
(parasitic)
- flagella buried into cytoplasm
- undulating membrane -> Moves through viscous fluids Parabasal bodies (the Golgi apparatus of the cell)
- Characteristics of Dicicristates
Protozoa - ingest food and move (animal like)
- Disk-shaped mitochondrial cristae
- Single-celled
- Highly Motile Flagella
- Most photosynthetic
- Some parasitic
2a. Euglenoids
(Eu- “good”) (-glen- “eye”)
- (freshwater)
- Most are autotrophs
- Photosynthetic
- Pellicle
- 2 Flagella
- Eyespot
- Movement
2b. Kinteoplastids
- Heterotrophs
- Animal parasites
- 2 flagella
- kinetoplast
- Large DNA and protein deposit
- Characteristics of Alveolates
•Small, membrane bound vesicles called alveoli under plasma membrane
3a. Ciliophora
- Heterotrophs
- Swim using Cilia
- Complex cytoplasmic structures
- Pellicle Has two nuclei
- Micronucleus (all genes- reproduction)
- macronucleus (some genes- metabolism)
- Some parasitic
- some Symbionts
3b. Dinoflagellata
- Shell of cellulose plates
- spin-like swim using flagella
- primarily marine
- autotrophs and heterotrophs
- Phototrophs
- Major primary producer (corals depend on them)
- Some are bioluminescent
- Some cause red tides
- When coral stressed- coral bleaching
3c. Apicomplexa
- Non-motile animal parasites
- Apical complex - attach and invade host cells •reproduction: both sexual and asexual
- no food vacuole - absorb through plasma membrane
- Characteristics of Heterokonts
•Two different flagella
-smooth and hairy
•mostly on eggs and sperm
4a. Oomycota (water moulds)
•Fungus- like water moulds, white rusts, downy mildews
- live as saprophytes or parasites
- grow as masses of hyphae
- >Form a network called mycelium
- secrete enzymes to digest organic matter
- sexual and asexual reproduction
4b. Bacillariophyta: Diatoms
- Photoautotrophs
- Carbon-fixing marine plankton
- Bilateral and radial
- Asexual and sexual reproduction
4c. Chrysophyta: Golden Algae
•Moslty photoautotrophs
•Not enough light -> heterotrophs
•Colonial forms
-Each cell with pair of flagella
•Brown colouring from Fucoxanthin
4d. Phaeophyta: Brown Algae
- Photoautotrophs
- multicellular marine forms
- Contain fucoxanthin, algin
•Kelps: Largest, most complex protists
- Differentiated structures:
- Blades
- Stipes
- Holdfasts
•Alternation of generations:
Sporophyte (diplod) and gametophyte (haploid)
- Characteristics of Cercozoa
- Amoebas
- Single-celled
- Move by stiff, filamentous pseudopodia
- Many produce hard outer shells - tests
5a. Radiolaria: Radiolarians
- Marine heterotrophs
- Glassy internal skeleton
- Axopods
- Raylike cytoplasmic structures
- Provide buoyancy
- Used in feeding
5b. Foraminifer: Forams
- Marine heterotrophs
- Cytoplasm extends through perforations in shells
- traps prey
- Spiral shells containing calcium carbonate
- Some with algal symbiont
5c. Chlorarachniophyta
•Autotrophs
- Contain chloroplast -> photosynthetic
- Also heterotrophs
-> filamentous pseudopodia – engulf food
- Characteristics of Amoebozoa
a. Amoebas
- Most amoebas
b. Slime moulds
i. Cellular
ii. Plasmodial
- Complex life cycle
- fruiting bodies forms spores by asexual or sexual reproduction
6a. Amoebas
- Most amoebas
- Marine, freshwater, soil
- Heterotrophs
- Some parasitic -> amoebic dysentery
- Unsupported pseudopod
- Asexual -> binary fission
- Single-celled
6b. Slime Moulds
Cellular slime moulds
- Single and multicellular
- Fruiting body – holds spores
- Sexual
- Meiosis->haploid
- Fusion->diploid
- Asexual->haploid
- Plasmodal slime moulds
- Plasmodium - Mass of cytoplasm with many nuclei
- Fruiting bodies – hold spores
- nuclei enclose into single cells
- Meiosis ->haploid spores
- Fusion -> diploid zygote
- Characteristics of Archaeplastida
- Includes land plant and two protist groups
- all photoautotrophs
7a. Rhodophyta: The Red Algae
- Most small marine seaweeds
- Typically multicellular
- Plant-like bodies
- stalks and leaf-like blades
- cell walls of cellulose and pectin
- Accessory pigments phycobilius
- Alternation of generations but no flagellated gametes
