PROTOZOA

Concepts/Ideas/Notes:

1. all protists are eukaryotic
2. all protozoa are heterotrophic
3. most freshwater organisms are hypertonic to their environment and water diffuses into them

Definitions:

1. Zooplankton – unicellular heterotrophic organisms that drift in water
2. Pseudopodia – cytoplasmic extensions that function in movement
3. Ectoplasm – thin, slippery colloidal sol directly inside the cell membrane
4. Endoplasm – is the colloidal sol and gel found in the interior of the cell
5. Ameboid Movement – cytoplasmic streaming, the internal flowing of the contents of a cell
6. Contractile Vacuole – organelle that excretes water
7. Phagocytosis – engulfing of food
8. Food Vacuole – portion of the membrane that surrounds food and pinches off
9. Exocytosis –
10. Cysts – dormant cell surrounded by a hard layer for protection
11. Cilia – short, hair-like projections that line the cell membrane and beat in synchronized strokes.
12. Pellicle – rigid protein covering
13. Macronucleus – controls such cell activities as respiration, protein synthesis, digestion, and asexual reproduction
14. Micronucleus – involved in sexual reproduction and heredity
15. Oral Groove – funnel-like grove lined with cilia which sweep food in
16. Mouth Pore – food swept in from the oral grove
17. Gullet – forms food vacuoles that circulate throughout the cytoplasm
18. Anal Pore – opening where waste is eliminated
19. Avoidance Behavior – reaction away from a potentially harmful situation

Kingdom Protists

Phylum Protozoa

Class

Sarcodina - ameba

1. move by pseudopodia
2. reproduce asexually by binary fission

Ciliophora - paramecium

1. move by the use of cilia
2. live in marine and freshwater habitats
3. surrounded by a rigid protein covering called a pellicle
4. have two kinds of nuclei – macronucleus and a micronucleus
5. have oral groove which sweeps food down the oral grove to the mouth pore
6. asexual binary reproduction
7. sexual reproduction by conjugation

Zoomastigina (Mastigophora)

1. have one or more long flagella

A.      Genus Trypanosoma – carry diseases

1.   slender, elongated, flattened protozoa with one posterior           flagellum

2.   carry diseases – sleeping sickness (T. gambiense & T.               rhodesiense)

3.   live blood of their hosts

                        4.   passed from host to host by blood sucking invertebrates like                               flies

B.       Genus Leishmania – Leishmaniasis

1.      carried by sand flies

2.      disfiguring skin sores and even death

C.      Genus Giardia – Giardiasis

1.      carried by muskrats and beavers

2.      fatigue, diarrhea, cramps, and weight loss                            

Sporozoa

1. are immobile and parasitic
2. carried in blood and other body fluids of host

A.      Toxoplasma – toxoplasmosis

1.  in animals (cats and dogs) it causes diarrhea

      2.   in humans it can affect brain, heart, liver, and eyes and be fatal.

B.       Plasmodium – malaria

1. carried by mosquito
2. destroys red corpuscles (erythrocytes)
3. fever, anemia, enlarged liver and spleen
4. often fatal

Characteristics of Protozoa:

1. most lack a protective outer covering
2. eyespots – localized regions of pigment that detects changes in the quantity and quality of light
3. can sense chemical changes in the environment
4. have semipermeable membrane
5. most are unicellular