Systematic Protozoology Quiz for 3rd Level Students

Study Notes

Systematic Protozoology

Study of identification, description, nomenclature, and classification of animals, including parasites, their hosts, and relationships between them.

History of Discovering Protozoa

Antony Van Leeuwenhoek (1632-1723)
Louis Pasteur (1857)
Michael Lewis (1879)
Louis Alphonse Laveran (1880)
Patrick Manson (1894)
Ronald Ross (1898)
Ernest Edward Tyzzer (1875-1965)

Protozoa

Unicellular or acellular animals
Eukaryotic, unicellular, and very small organisms
Most species are microscopic, but a few can be seen with the naked eye
Protozoan cell is larger and more complex than prokaryotic cell, with various organelles
Only one nucleus in the cytoplasm with a distinct nucleolus (endosome)
Cytoplasm is differentiated into an outer ectoplasm and inner endoplasm

Movement in Protozoa

Two types of movement:
- Pseudopodia (Ameboid movement)
- Cilia and flagella (morphologically different, but structurally the same)
Examples:
- Paramecium (moves by cilia)
- Euglena (moves by flagella)

Reproduction in Protozoa

Conjugation: a type of sexual reproduction in ciliates (e.g., Paramecium) involving temporary plasma membrane fusion and exchange of genetic material
Gamontogamy: a type of sexual reproduction in Protozoa

Environmental Response in Protozoa

Two types of response:
- Behavioural response:
  - Example: Amoeba's contractile vacuole to remove excess salts
  - Example: Paramecium's avoidance reaction
- Morphogenetic response:
  - Example: Naegleria's response to environmental changes, including encystation and production of flagella

Mode of Life (Living)

Two types of protozoans:
- Free-living protozoans (e.g., Euglena, Amoeba, Paramecium) that obtain food themselves
- Commensal protozoans (e.g., parasitic protozoans that feed on other organisms)

Protozoan Parasites

Examples:
- Balantidium coli: a protozoan parasite that inhabits the caecum and colon of humans
- Nyctotherus: a protozoan parasite that lives inside the colon of toads and frogs
- Blepharisma: a genus of unicellular ciliate protists found in fresh and salt water
- Stentor and Vorticella: stalked ciliates that inhabit freshwater environments and moist soil, mud, and plant roots
- Trichodina: a genus of ciliate alveolates that are ectoparasitic on aquatic animals, particularly fins and gills of fishes

Phylum Dinoflagellata

Single-celled organisms that are neither animals nor plants
Most species have two flagella, with or without plastids
Dinoflagellates produce a neurotoxin that affects muscle function in susceptible organisms
Systematics: classified into two subphyla, Dinokaryota and Syndinea, with multiple classes and genera

Phylum Myxozoa

Examples:
- Myxosporea: parasitize vertebrates (fishes and amphibians)
- Actinosporea: parasitize invertebrates (Annelids)
Myxozoan spores contain from 1-8 polar capsules each with polar filaments capable of attaching to host tissues

Phylum Microsporea

Obligate intracellular parasites of fishes
Structure of microspores consists of one polar capsule bearing one polar filament
Examples:
- Pleistophora spp.: found in muscle of fishes and reptiles
Infective stage: resistant spore that can persist in the environment for months
Life cycle: spore germination, polar tubule ejection, sporoplasm injection, and sporogony

Phylum Labyrinthomorpha

Small phylum with spindle-shaped cells, about 10μm long
Reproduce both asexually and sexually
Most species are marine, some forming colonies on algae and seagrasses, causing grass diseases

Phylum Ascetospora

Unicellular eukaryotes that are parasites of animals, especially marine invertebrates

Description

Test your knowledge of protozoa, a branch of zoology that deals with the study of identification, description, and classification of different kinds of animals, including parasites and their hosts. This quiz is designed for 3rd level students.