kingdom protista -...
TRANSCRIPT
KINGDOM PROTISTA
“The Junk Drawer” of Classification
•Classified based on what they are NOT – they are NOT fungi, plants, or animals, but they are eukaryotic (in fact, they were probably the FIRST organisms to evolve a nucleus)
•First to reproduce sexually; first multicellular organisms
•Most are unicellular & microscopic
•Live where ever there is moisture (water)
•Historically, divided into algae (plant-like) and protozoa (animal-like)
Types of Protists
Use the following slides to complete the table in your notes. Look for:
* Distinguishing characteristics
* How they obtain nutrition
* Examples and illustrations
Types of Protists
• Ameboids
– Amoeba
– Foraminifera
• Algae
– Green
– Red
– Brown
• Diatoms
• Flagellates
– Dinoflagellates
– Euglenoids
– Kinetoplastids
– Cilliates
• Molds
• Sporozoans
Ameboid: Ameoba (phylum Rhizopoda)
• No cell wall, no flagella, extremely flexible
• Pseudopodia: for eating and motility
Pseudo = “false” podium = “feet”
• Heterotrophic: engulf prey with pseudopodia by endocytosis/phagocytosis
• Reproduction:
mostly asexual
through binary fission
Amoeba engulfing a paramecium with pseudopodia – An example of phagocytosis (a form of heterotrophy)
Ameboid: phylum Foraminifera
• note the long pseudopodia coming out of the shell of calcium carbonate
• nutrition: heterotrophic and photosynthetic (depending on the species)
• compose sedimentary rock
Ameboid: Heliozoans and Radiolarans
• Related to amoebas – pseudopodia & phagocytosis
• Long, slender pseudopodia coming from the heliozoan on the left
• Heliozoans are freshwater; radiolarans are marine (saltwater)
• Both form the ooze on the floor of these bodies of water with the shells left from their dead bodies
Phylum Algae
• Autotrophic: photosynthesis
• Unicellular or multicellular
• Named according to pigment
– Pigment is what makes color
• Produce 1/3 of oxygen in atmosphere (more than the plantae kingdom)
25 nm
60 m
Golden algae - microscopic Brown algae - macroscopic; this is a kelpforest, supplying habitat and food for an entire ecosystem
multinucleate green algae; these
are NOT leaves
Volvox (microscopic)
Red Algae Green Algae
Diatoms: Phylum Bacillariophyta
• Photosynthetic
• Unicellular
• Two part shell (like a box and lid) made of silica
• When the shell separates, each half regenerates another matching half
• Shell deposits are mined and used for commercial purposes
Flagellates: phylum Euglanoid
• Use flagella for motility
• Have an eyespot for phototaxis
• Have a contractile vacuole for water balance
• Autotrophic/ photosynthetic (chloroplasts) AND heterotrophic
Flagellates: phylum Dinoflagellate
• Photosynthetic AND heterotrophic
• Planktonic, phytoplankton (phyto = plant)
• Responsible for red tide (named for the photosynthetic pigment they contain); “blooms” of these organisms cause massive kills due to the toxins they produce
• Heterotrophic species use the toxins to stun prey (like fish) and then feed on its body fluids
• Some are bioluminescent (bio = life, lumin = light)
• Also related to the euglenoids (note the presence of the flagella)
Phylum Flagellates: • Trypanosoma – genus of the protist that causes African sleeping
sickness in humans (host) following the bite of the tsetse fly (vector)
• Giardia – genus of another flagellated protist that causes disease in humans
• Closely related to the euglenoids because they have similar body coverings
Paramecium: phylum Ciliophra All members of this group have cilia. Note there are even cilia lining the oral groove
*contractile vacuole
*micro and macro nuclei
*Heterotrophic – food enters through oral groove, food vacuole forms, lysosomes help digest food
LOOK! Waste leaving cell (exocytosis)
Ciliophorans: Stentor and Paramecium
Slime molds: phylum Myxomycota
• Protists that aggregate (clump together) in times of stress to form spore-producing bodies
• Look like fungi but are NOT (no chitin in cell walls)
• Heterotrophic – engulf bacteria and organic material
Molds: plylum Oomycota
• heterotrophic
• commonly found in very wet environments growing on dead or decaying orgahnisms, such as on the fish below; called “mycota” because they look like fungi but are NOT (no chitin in cell walls)
• Many are pathogenic
– Late blight was responsible for the Irish potato famine
Sporozoan: phylum Apicomplexa
CHARACTERISTICS
• Spore-forming
• Non-motile
• Unicellular
• Parasitic
DISEASES
• Malaria: host – vertebrates; spread by mosquitoes
• Toxoplasmosis: host – humans & cats
• Cattle tick fever: host – cattle, mice, humans, deer, dogs
• Cryptosporidiosis: host – cattle humans, birds, deer, dogs, cats
Malaria sporozoans of genus Plasmodium
Protista Vocabulary This list may not be complete for YOU.
If you don’t know these words (or any others in this unit), look them up or ASK!
Colony Nonmotile/motile/sessile
Aggregation Conjugation
Multicellular Alternation of generations
Complex multicellularity Heterotroph/autotroph
Pseudopodia Photosynthetic
Flagella Gamete
Cilia Spore
Planktonic/plankton Host
Silica Vector
Spore Parasitic/saprophytic
Phototaxis Contractile vacuole
Rhizopoda
Amoeba, related organisms
Flexible, no cell wall, pseudopodia, related – shells
Heterotrophs – phagocytosis
p. 464
Euglenophyta
Euglena and related flagellates
Flagella
Eye spots
Autotrophic – photosynthetic & heterotrophic
p. 467
Ciliophora
Paramecium and related ciliates
Cilia
Contractile vacuole
Oral groove
Heterotrophic p. 469
Dinoflagellates Planktonic
Flagellated
Toxic – red tide
Heterotrophic & autotrophic/photosynthetic
p. 467
Bacillariophyta
Diatoms
Shells of silica
Shoe box like shell
Planktonic
Photosynthetic p. 466
Algae (golden, brown, red & green)
Many multicellular Photosynthetic p. 461, 465
“-mycota” groups; water molds & slime molds
Fungus-like
Some aggregate in times of stress; spores
Heterotrophic p. 470
Sporozoans
Complex life cycle - Apicomplexa
nonmotile, unicellular, parasitic, spore-forming, disease-causing
Heterotrophic p. 471 & p. 473