Protozoans

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Protozoans
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Classification

• There are six kingdoms
• Domain Bacteria Kingdom Eubacteria
• Domain Archaea Kingdom Archebacteria
• Domain Eukarya four kingdoms
• Protista
• Fungi
• Plantae
• Animalia

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Porifera
Platyhelmithes
Mollusca
Arthropoda
Hemichordata
Echinodermata
Cnidaria
Nemertea
Annelida
Chordata
Lophophores
Pseudocoelomates
Protozoans
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Numbers of species
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General considerations

• Unicellular heterotrophs, a few are colonial
• Cells that are much more complex than normal
  animal cells
• Characterized by the way they move

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Kingdom Protista

• This kingdom is very diverse in habitat and life
  form. The kingdom includes unicellular
  organisms, large multicellular algae and
  plasmodial slime molds.

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Protist phyla - protozoans

• Phylum Sarcomastigophora- flagellates and
  amoeboid protozoa
• Subphylum Mastigophora- flagellates
• Subphylum Sarcodina- amoeboid
• Phylum Ciliophora- ciliates
• Phylum Apicomplexa- spore-forming parasites

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Protist phyla - protozoans

• examples to look for
• Paramecium (Ciliophora) is a typical ciliate,
  which contains a large darkly stained
  macronucleus
• Amoeba (Sarcodina) has many pseudopodia for
  locomotion and food capture
• (continued.)

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Amoeba
Nucleus
Food Vacuoles
Endoplasm
Water expulsion vesicle
Pseudopodia
Ectoplasm
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Amoeboid locomotion
Ectoplasm
Endoplasm
Hyaline cap
Direction of movement
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Pseudopodial types

• Lobopodia
• Filopodia
• Reticulopodia
• Axopodia

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Protist phyla - protozoans

• Foraminiferans (Sarcodina) marine secrete a
  calcareous shell (test)
• test forms spiral patterns
• Radiolarians (Sarcodina) marine secrete
  siliceous (glass-like) tests
• tests are extremely fragile and are often only
  seen as fragments

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Protozoan skeletons

• Chitin
• Calcium Carbonate
• Foraminifera
• Silica
• Radiolarians

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Protozoan skeletons

• Chitin
• Calcium Carbonate
• Foraminifera
• Silica
• Radiolarians

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Protozoan skeletons

• Chitin
• Calcium Carbonate
• Foraminifera
• Silica
• Radiolarians

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Euglena
Flagellum
Eyespot
Nucleus
Nucleolus
Pellicle
Paramylon grains
Chloroplast
Paraflagellar body
Water expulsion vesicle
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Protist phyla - protozoans

• Trypanosomes (Mastigophora) are parasitic
  flagellates living in the blood of vertebrates
  disease example African sleeping sickness
• Plasmodium (Apicomplexa) is a parasite living
  within the blood of mammals and birds that causes
  malaria

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Trypanosomes
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Protist phyla - protozoans

• The movement of the organism can indicate the
  type of locomotion.
• ciliates tend to have fast, smooth motion
• flagellates are often slower with an almost
  spiraling motion and
• those using pseudopodia are slow and have an
  oozing, liquid movement.
• Special note remove Volvox from list on page
  1.8 it should be in Chlorophyta, NOT
  Sarcomastigophora

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Compound ciliature
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Euplotes
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Myonemes
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Phagocytosis
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Paramecium
Cytoproct
Food Vacuole
Cytostome
Cytopharynx
Oral Groove (Peristome)
Water expulsion vesicle (empty)
Pellicle
Micronucleus
Macronucleus
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Compound ciliature
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Digestion
Cytoproct
Cytostome
Food vacuole
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Water expulsion vessicle
Excretory pore
Ampulla
Endoplasmic reticulum
Feeder canal
Empty
Full
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Reproduction

• Sexual reproduction
• Conjugation
• Asexual
• Binary fission
• Multiple fission

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Protist phyla - algae

• Phylum Chlorophyta- green algae
• Phylum Phaeophyta- brown algae
• Phylum Rhodophyta- red algae

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Phylum Chlorophyta- green algae

• largest phylum of algae
• very diverse in life form, size and complexity
  ranging from unicellular to colonial to
  filamentous to thallus bearing (simple vegetative
  body, no true roots, stems or leaves)
• some green algae can be stretch for several feet

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Phylum Chlorophyta- green algae

• Gonium and Volvox are motile, colonial green
  algae.
• Gonium colonies are flattened and are held
  together by gelatinous material
• Volvox colonies are large spheres usually within
  the sphere are several conspicuous daughter
  colonies

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Volvox
Sperm
Zygote
Zygote
Egg
Sperm
Daughters (Sons)
Body cell
Sexual
Asexual
Parent
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Conjugation
Conjugates join at the oral area and the
micronucleus undergoes meiosis
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Conjugation
4 micronuclei are formed, Macronucleus remains
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Conjugation
Micronuclei are exchanged Macronucleus remains
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Conjugation
Two macronuclei and macronucleus disappear
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Conjugation
Synkaryon forms from thefusion of micronuceli in
each conjugant.
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Conjugation
Three mitotic divisions produce 8 nuclei
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Conjugation
4 micronuclei become macronuclei, 3
disappear, and remaining become Micronucleus.
Brusca and Brusca 5.31
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Conjugation
Mitotic divisions of micronuclei and macronucleus
Brusca and Brusca 5.31
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Malaria - human
Sporogony
RBCs
Liver
Gametogony
Schizogony
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Malaria - human
Oocysts beneath stomach lining
Sporozoites migrate to the salivary glands
Female gamete
Sporogony
Male gamete
Mosquito's saliva infects human
Ingestion of gametocytes
RBCs
Liver
Gametogony
Schizogony
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Malaria - human
Sporogony
Ingestion of gametocytes
Sporozoites enter liver cells
Macrogametocyte
Microgametocyte
RBCs
Liver
Gametogony
Schizont
Schizogony
Trophozoite
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Colonial protozoans
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Colonial choanoflagellate
Flagellum
Collar of Microvilli
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Phylum Phaeophyta- brown algae

• include marine seaweed and kelps
• have large, multicellular, complex bodies that
  form a flattened blade, stipe (stalk) and
  holdfast
• kelp forests are important marine ecosystems,
  typically found in cool or cold, nutrient rich
  areas

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Phylum Rhodophyta- red algae

• multicellular and marine
• often found in deep waters due to their extreme
  efficiency at capturing red, green and blue light
  waves
• also found in tropical waters, contributing to
  the formation of coral reefs (coralline algae)
• complex body is often comprised of interwoven
  cells

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Protist phyla slime molds

• Phylum Myxomycota- plasmodial slime molds
• ooze on the forest floor
• non-walled, multinucleate masses of protoplasm
  called a plasmodium
• plasmodium is a feeding stage
• in harsh conditions the plasmodium enters an
  alternate life form in which sporangia (stalked
  fruiting bodies) are produced
• Example Physarum (yellow, in Petri dishes)