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Protists are unicellular organisms that have a nucleus. They can cause disease and be parasites. They are divided into animal-like, plant-like, and fungus-like categories. Animal-like protists include sarcodines, ciliates, flagellates, and sporozoans. Plant-like protists include euglenoids, diatoms, dinoflagellates, red algae, green algae, and brown algae. They play a vital role in producing oxygen and have diverse appearances and functions.
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Protists Kingdom: Protista Protists are unicellular organisms that have a nucleus.
Similar to Bacteria • Unicellular • One of the first groups of living things on Earth. (1.5 billion years ago.) • Microscopic • Can cause disease. • Can be parasites Same
Difference from Bacteria • Has a nucleus. • Live in watery environment. • Generally live as individual cells. • Protists vary greatly in appearance and function. Different
3 Categories • I. Animal-like Protists. • II. Plant-like Protists. • III. Fungus-like Protists.
I. Animal-like Protists • Protozoan means “First Animal”. • Cells contain a nucleus. • Cells lack a cell wall. • They are heterotrophs. • Most can move on their own. Little Animals
4 Groups of Animal-like Protists • 1. Sarcodines (SAHR-koh-dighnz) • 2. Ciliates (SIHL-ee-ihts) • 3. Flagellates (FLAJ- ehl-ihts) • 4. Sporozoans (spohr-oh-ZOH-uhnz)
1. Sarcodines • Have pseudopods (Greek:“false foot”) • Extensions of the cell membrane and cytoplasm. • Pseudopods are used for movement and to capture food. • Many have shells. • These shells form limestone, marble and chalk.
One type: Amoeba • Most familiar Sarcodine. • Pseudopods: • Blob shaped. • Contractile Vacuoles: controlsamount of water inside • Food Vacuole: where food is digested.
Split Personality • Reproduce by binary fission • Amoebas can respond to their environment. • They are sensitive to light and some chemicals.
2. Ciliates • Have cilia on the outside of their cells. • Tiny hair-like projections used for movement, to gather food and as feelers.
Type: Paramecium • Pellicle: tough outer wall. • Slipper shaped • Oral groove: like the mouth • Gullet: holds food. • Food Vacuole: digests food.
Type: Paramecium • Anal Pore: removes wastes • 2 Contractile Vacuoles • 2 Nuclei • Reproduces by either binary fission or conjugation.
3. Flagellates (Zooflagellates) • Have a Flagellum: a long whip-like structure used for movement. • Many live in animals • Symbiosis a close relationship, at least one benefits. • Mutualism: when both partners benefit.
4. Sporozoans • All Sporozans are parasites. • They feed on cells and body fluids. • Form from Spores (tiny reproductive cells). • Pass from one host to another. • Pass from ticks, mosquitoes or other animals to humans.
II. Plant-like Protists(Algae) • Unicellular and Multicellular • Colonies (groups of unicellular protists) • Can move on their own • Autotrophs: make their own food from simple materials using light energy (photosynthesis). • 70% of the Earth’s oxygen is produced by Plant-like Protists! • Pigments: chemicals that produce color
6 Groups of Plant like Protists • Euglenoids (yoo-GLEE-noydz) • Diatoms (DIGH-ah-tahmz) • Dinoflagellates (digh-noh-FLAJ-eh-layts) • Red Algae • Green Algae • Brown Algae
1. Euglenoids • Green • Unicellular • Live in fresh water • Autotrophs, but can be heterotrophs under certain conditions. • Flagella • Eyespot: sensitive to light. • Chloroplasts • Pellicle
Green Algae • Most are unicellular • Some form colonies • Few are multicellular • Can live in fresh and salt water and on land in damp places. • Very closely related to green plants.
