1. Protozoa Over all View

2. V.PARTHASARATHY Lecturer in Zoology Vivekananda College,By
V.PARTHASARATHY
Lecturer in Zoology
Vivekananda College,
Tiruvedakam West

3. Characteristics of Protozoa
Unicellular Organization
Since Protozoa are single celled they often rely on other organisms for some necessities
Reproduction:
Asexual:
binary fission: cytoplasmic division follows mitosis, producing two organisms
budding:
multiple fission or schizogeny: cell or organism is split into many new cells or organisms
Sexual

4. Reproduction

5. Symbiosis: an intimate association between two organisms
Three types of symbiosis:
Parasitism: one organism lives in or on a second organism, called the host.
the host is harmed, but usually survives
Commensalism: one organism benefits and the other neither benefits nor is harmed
Mutualism: both organisms benefit from the relationship

6. Protozoan Taxonomy Phylum Sarcomastigophora Phylum Apicomplexa
Subphylum Mastigophora
Subphylum Sarcodina
Phylum Apicomplexa
Phylum Ciliophora

8. SARCOMASTIGOPHORA

9. Phylum Sarcomastigophora: 18,000 species, largest protozoan phylum
Characteristics:
Unicellular or Colonial
Locomotion by flagella, pseudopodia, or both
Autotrophic, saprozoic, or heterotrophic
Single type of Nucleus
Sexual Reproduction (usually)

10. LOCOMOTION

11. Subphylum Mastigophora: locomotion by one or more flagella

12. Subphylum Sarcodina: locomotion and food gathered by pseudopodia (false foot) - includes the Amoeba

13. Pseudopodia - temporary cell extension used for movement and gathering food
Types:
Lobopodia: broad extensions used for locomotion and engulfing food
Filopodia: provide constant two-way streaming that delivers food in a conveyor belt fashion
Reticulopodia: similar to filopodia, except they extend out and form net-like series of extensions
Axopodia: thin, filamentous and supported by a central axis of microtubules

14. The AMOEBA

16. APICOMPLEXA

17. Phylum Apicomplexa: Characterisitics: All are parasites
Apical Complex for penetrating host cells
Single type of Nucleus
Usually No Cilia and Flagella
Life cycles that typically include asexual and sexual phases

18. Malaria caused by Plasmodium

19. Phylum Ciliophora: Characteristics:
Cilia for locomotion and for the generation of feeding currents of water.
Relatively rigid pellicle and more or less fixed shape
Distinct cytostome (mouth) Structure
Dimorphic nuclei, typically larger macronuclei and one more smaller micronuclei

20. Ciliophora

21. Locomotion: cilia
Cilia are generally similar to flagella but are much shorter, more numerous and widely distributed over the surface of the organism
cilia have evolved into more specialized structures
Trichocysts: used for protection, rodlike or oval structures that can be discharged and stuck to predators

22. Trichocysts

23. Body types

24. Nutrition: some ciliates possess an oral groove
cilia sweep food particles down this groove toward the cytopharynx where a food vacuole forms
some ciliates even possess an anal pore which is used to remove waste from the organism

26. Genetic Control and Reproduction:
Ciliate have two kinds of Nuclei
Macronuclei: large polyploid nucleus that regulates daily metabolic activities
Micronuclei: one or more small nucleus which are genetic reserve of the cell
Ciliates can reproduce asexually by transverse binary fission and occasionally by budding
Ciliates can reproduce sexually by conjugation

27. Conjugation:
Random contact brings individuals of opposite mating types together (called conjugants)
Meiosis results in four haploid pronuclei
Three pronuclei and the macronucleus degenerate. Mitosis and mutual exchange of pronuclei is followed by fusion of the pronuclei.
Conjugants separate. Nuclear divisions that restore nuclear characteristics of species follow. Cytoplasmic divisions may accompany these events

28. Conjugation