Kingdom Protista

These are eukaryotes and unicellular. They can be autotrophic or heterotrophic. They have pseudopodia, hair-like cilia, or whip-like flagella for locomotion and mostly live in aquatic or moist environments, such as ponds, lakes, and soil. They can reproduce both sexually (exchange of genetic material) and asexually (by dividing).

Autotrophs, e.g., Euglena and Volvox (contain chloroplast).
Heterotrophs, e.g., Amoeba and Paramecium.

Organisms from Kingdom Protista

1. Aim: To observe motile microbes, specifically amoebae, in a sample of pond water using a microscope.

2. Requirements: pond water sample, microscope (low and high power), glass slide, cover slip, dropper, tissue paper or blotting paper.

3. Procedure

• Place a drop of pond water on a glass slide.
• Cover it with a coverslip carefully.
• Remove excess water using tissue paper.
• Observe under low power, then switch to high power to view amoebae.

4. Conclusion

Motile microbes such as amoebae can be observed in a pond water sample. They are characterised by their irregular shape and constant movement, using extensions called pseudopodia for locomotion and capturing food.

1. Meaning - All single-celled eukaryotes act as a link between plants, animals and fungi; mostly aquatic; have a nucleus and membrane-bound organelles.

2. Chrysophytes - Includes diatoms and golden algae; cell wall has silica; deposits form Diatomaceous Earth (used in polishing and filtration); chief producers in oceans.

3. Dinoflagellates - Mostly marine, photosynthetic; cell wall of cellulosic plates; have two flagella (one longitudinal, one transverse); rapid multiplication of red dinoflagellates (e.g. Gonyaulax) causes red tides.

4. Euglenoids - Have a pellicle instead of a cell wall; photosynthetic in sunlight but become heterotrophs in its absence. e.g. Euglena.

5. Slime Moulds - Saprophytic; feed on decaying matter; undergo syngamy to form a plasmodium that spreads over several feet.

6. Protozoans - 4 types:

• Amoeboid - move by pseudopodia. e.g. Amoeba, Entamoeba
• Flagellated - have flagella; cause sleeping sickness. e.g. Trypanosoma
• Ciliated - have cilia; have a gullet for feeding. e.g. Paramecium
• Sporozoans - no locomotory organelle; all parasitic. e.g. Plasmodium