Protists are a very large, diverse group of organisms, including the plant-like protists (algae), fungi-like protists, and the animal-like protists (protozoans). They are all eukaryotic, and most are unicellular. Traditional taxonomy of protists (Kingdom Protista) did not accurately represent evolutionary relationships, so the classification of this group is unsettled. Modern taxonomy has rearranged the group formerly known as Kingdom Protista, separating the different types of organisms into their own candidate Kingdoms. Protists vary in how they obtain energy (autotrophic or heterotrophic) and in their locomotion. Locomotion
Movement is achieved by several different methods in the protists. Cilia - Microscopic hair like projections extending from the surface of a cell or unicellular organism. Capable of rhythmical motion, they act in unison to bring about the movement of the cell or of the surrounding medium Paramecium
Flagella - A long, threadlike appendage, especially a whip like extension of certain cells or unicellular organisms, found singly or in pairs. Euglena
Pseudopodia - A temporary projection of the cytoplasm of certain cells, such as phagocytes, or of certain unicellular organisms, especially amoebas. Amoeba
Protists are classified by how they acquire energy. Often a single method is specific to a single protist. There are four grouping of how energy is obtained.
Heterotroph by ingestion
Heterotroph by absorption
Photosynthetic autotrophs make their own food using energy from light to power complex chemical reactions to make glucose. Chemosynthetic autotrophs do the same thing using energy obtained from the breakdown of chemicals. Heterotrophs require food as they cannot make their own. Heterotrophs by ingestion eat by consuming food; taking it into their bodies to be digested by enzymes. Nutrients are then released from within the...
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