Chapter 3, Section 1 – Protists
I. What is a Protist?
a. eukaryotes – cannot be classified with plants, animals, or fungi b. live in moist surroundings c. can be unicellular (most) and multicellular (some) d. heterotrophs, autotrophs, or both e. some can move while some cannot f. grouped or divided into three categories: i. animal-like protists ii. plantlike protists iii. funguslike protists
II. Animal-like Protists – classified into four groups based on how they move and live a. Protozoans with Pseudopods: i. pseudopod means “false foot” ii. moves because of the flow of cytoplasm iii. pseudopods can be used to move and to trap food iv. contractile vacuole: collects extra water and then removes it from the cell v. example: amoeba b. Protozoans with Cilia i. ciliates – second group of animal-like protists ii. cilia – hairlike structures that move in a wavelike motion iii. cilia – help ciliates to move and obtain food iv. example: paramecium (has two contractile vacuoles and two nuclei)
1. large nucleus: controls cell’s everyday tasks
2. small nucleus: functions in reproduction c. Protozoans with Flagella i. flagellates – third group of animal-like protists ii. flagella: long, whiplike structure, used in movement iii. some flagellates live in other organisms (ex: termites) iv. symbiosis: relationship in which at least one species benefits v. mutualism: relationship in which both species benefit from living together vi. occasionally, protozoans can harm their host (ex: hiker’s disease) d. Protozoans that are Parasites i. characterized by the way they live ii. feed on the cells and body fluids of their hosts iii. move in various ways (even slime) iv. example: Plasmodium

Chapter 3, Section 1 – Protists
III. Plantlike Protists (commonly called algae) a. Diatoms i. unicellular protists – glasslike cell walls ii. live on the surface of lakes or oceans or attach to rocks in shallow water iii. food source for heterotrophs that live in water iv. many can move by using slime to glide along v. form diatomaceous earth when they die b. Dinoflagellates i. unicellular algae surrounded by stiff plates (looks like armor) ii. exist in many colors iii. have two flagella used in moving iv. some dinoflagellates glow in the dark c. Euglenoids i. green, unicellular algae (found mostly in freshwater) ii. have one animal-like characteristic (can be heterotrophs when no sunlight is present) iii. example: euglena – have flagellum and an eyespot to detect light sources d. Red Algae i. multicellular seaweed ii. found at extreme d epths below the ocean’s surface iii. red pigments are good at absorbing light from deep in the ocean iv. used as a food product, or in making products such as ice cream and hair conditioner e. Green Algae i. contain green pigments and are typically unicellular ii. some form colonies or are multicellular iii. most live in fresh or salt water, some live on rocks, bark, or soils iv. sometimes considered part of the plant kingdom f. Brown Algae i. commonly called seaweed ii. contain brown, green, yellow, and orange pigments iii. has many plantlike structures (stalks, anchors, etc.) iv. usually grow best in cool, rocky waters v. used as a food source and in producing foods
IV. Funguslike Protists a. heterotrophs with cell walls, b. reproduce with spores

Chapter 3, Section 1 – Protists c. all types are able to move at some point in their lives d. three types of funguslike protists: i. Slime molds:
1. live in moist, shady places
2. move by oozing along decaying materials
3. feed on bacteria or other microorganisms ii. Water molds and downy mildews
1. live in water or moist places
2. grow as tiny, threadlike “fuzz”
3. often attack food crops (ex: Irish potato famine)