Kingdom Protista

The Kingdom Protista includes mostly unicellular eukaryotes such as protistan algae, Slimemoulds and Protozoans.

On evolutionary point of view this kingdom acts as as a connecting link between prokaryotic monera and multicellular eukaryotic kingdom.(fungi, plant and  animals )

Examples: Euglena, Paramecium , Gonyaulax,

Diatoms, Amoeba, Entamoeba

General Characters:

Euglena like protists show a double life; auto trophic and heterotrophic.

Many of the protists are photosynthetic autotrophs found mainly in fresh water and oceans. They are called phytoplankton e.g. diatoms.

Structure: Mostly unicellular and posses typical cell organelles like nucleus, mitochondria, endoplasmic reticulum (ER), Golgi bodies and plastids.

Locomotion:  Some of them have cilia or flagella with 9+2 internal microtubular structure.

Reproduction: Asexual Methods ( Binary Fission, Multiple fission, budding and spore formation) and Sexual methods.

Life Cycles: Zygotic Meiosis and Gametic Meiosis

Major groups of Protists

1. Photosynthetic Protists

         Examples: Dinoflagellates, Diatoms and Euglenoids)

2. Slime moulds

• Cellular ( Dictyostelium)
•   Acellular (Physarella and Physarum)

3. Protozoan Protists

• Zooflagellates (Trypanosoma, Leishmania, Trichomonas, Trichonympha)
• Amoebae (Amoeba, Entamoeba)
• Sarcodines (Radiolarians and Foraminiferans)
• Ciliates (Paramecium, Opalina, Vorticella)

For More:

• MCQ on Kingdom Protista