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Section 20-1: The Kingdom Protista
Protists are eukaryotes that are not members of the kingdoms Plantae, Animalia, or Fungi.
Section 20-2: Animallike Protists: Protozoans
Animallike protists that swim using flagella are classified in the phylum Zoomastigina and are often referred to as zooflagellates.
Sarcodines are animallike protists that use pseudopods for feeding and movement.
Members of the phylum Ciliophora, known as ciliates, use cilia for feeding and movement.
Members of the phylum Sporozoa do not move on their own and are parasitic.
Some animallike protists cause serious diseases, including malaria and African sleeping sickness.
Section 20-3: Plantlike Protists: Unicellular Algae
Chlorophyll and accessory pigments allow algae to harvest and use the energy from sunlight.
Euglenophytes are plantlike protists that have two flagella but no cell wall.
About half of dinoflagellates are photosynthetic; the other half live as heterotrophs.
Members of the phylum Chrysophyta are a diverse group of plantlike protists that have gold-colored chloroplasts.
Diatoms produce thin, delicate cell walls rich in silicon (Si)—the main ingredient in glass.
Section 20-4: Plantlike Protists: Red, Brown, and Green Algae
Red algae are able to live in great depths due to their efficiency in harvesting light energy. Red algae contain chlorophyll a and reddish accessory pigments called phycobilins.
Brown algae contain chlorophyll a and c, as well as a brown accessory pigment, fucoxanthin.
Green algae share many characteristics with plants, including their photosynthetic pigments and cell wall composition.
The life cycles of most algae include both a diploid and a haploid generation.
Section 20-5: Funguslike Protists
Funguslike protists lack chlorophyll and absorb nutrients from dead or decaying organic matter. But unlike most true fungi, funguslike protists have centrioles. They also lack the chitin cell walls of true fungi.
Slime molds are funguslike protists that play key roles in recycling organic material.
Oomycetes thrive on dead or decaying organic matter in water and are plant parasites on land.