Interest Grabber Section 20 1 Food for Thought

Interest Grabber Section 20 -1 Food for Thought • What do you do when you get hungry? You probably go in search of food. Different organisms have different ways of obtaining the nutrients they need to live. 1. How does an animal obtain food? 2. How does a plant obtain food? 3. Predict how a microorganism described as “plantlike” might behave. Go to Section:

Concept Map Section 20 -1 Protists are classified by Animallike Plantlike which Take in food from the environment Produce food by photosynthesis Obtain food by external digestion Go to Section: Funguslike which include Decomposers Parasites

Interest Grabber Section 20 -2 On the Move • Think about the last time you watched a puppy at play, a fish in an aquarium, or a squirrel in the park. They don’t stay still for long. How do they get where they are going? 1. List five different ways in which animals can move from place to place. 2. What structures do these animals have that enable them to move? 3. What structures might a microorganism need in order to move? Go to Section:

How Are Protists Classified • Mainly by the way they move, how they obtain nutrients (animal-like, plant-like, fungus-like) – Movement: pseudopods, cilia, flagella – Obtaining Nutrients: autotrophic (plant-like)or heterotrophic (animal-like, fungus- like) Go to Section:

Section Outline Section 20 -2 • 20– 2 Animallike Protists: Protozoans A. Sarcodines B. Ciliates C. Sporozoans- Animallike Protists and Disease 1. Malaria 2. Other Protistan Diseases D- Zooflagellates Go to Section:

Life Processes and Lifestyle of a Sarcodines • Cell Type: Eukaryotic, unicellular • Where they live: water environment (freshwater and marine) • Mode of Nutrition: Heterotrophs, engulfs food • Reproduction: mainly asexually • Movement: Pseudopods via cytoplasmic streaming • Examples: Ameoba Go to Section:

Sarcodine Example: Amoeba. Section 20 -2 Contractile vacuole Pseudopods Nucleus Food vacuole Go to Section:

The Ameoba ontractile vacuole • Main Structures • Pseudopods: “false feet”- uses them to move by cytoplasmic streaming. Also uses pseudopods to engulf food. • • Nucleus: control center, hereditary info Food Vacuole: stores food and nutrients • Contractile vacuole: regulates the amount of water and pumps out excess water and wastes Pseudopods leus vacuole Go to Section:

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Watch the ameoba movement • Ameoba Go to Section:

The Ciliates • Cell Type: unicellular, eukaryotic • Where they live : Water environment • Movement: cilia – short hair-like projections, similar to flagella that allow them to swim in their environment • Mode of Nutrition: heterotrophic- cilia sweeps in food from their surroundings, or food can enter through an oral groove • Reproduction: mainly asexual, can also by conjugation • Mostly free living – not parasitic • Examples: stentor, paramecium Go to Section:

Figure 20 -5 A Ciliate Section 20 -2 Lysosomes Trichocysts Oral groove Gullet Anal pore Contractile vacuole Micronucleus Macronucleus Go to Section: Food vacuoles Cilia

• Cilia- hairlike projections that aid in movement of the organism • Trichocysts- small bottleshaped structures used for defense. • Two nuclei- Micronucleus (cell divison) & Macronucleus • Oral groove: collects and directs food into gullet • Gullet- An indentation in one side of the organism that collects food. • Contractile Vacuolesspecialized to collect water. • Endoplasm: cytoplasm toward the middle of the cell Go to Section:

The Blepharisma- Another ciliate Go to Section:

• Paramecium life Go to Section:

Phylum Sporozoa - Sporozoans • Cell Type: eukaryotic and unicellular • Mode of Nutrition: heterotrophic (parasitic). Complete part of their life processes within a host cell • Movement: can not move by themselves. Rely on the host vector for transport, but can move within the vector • Reproduction: asexually within the host cell Go to Section:

Diseases that Sporozoans cause • Malaria • Caused by the sporozoan named Plasmodium vivax • Plasmodium’s host is the mosquito • Can use chloroquinine to help treat it • Malaria Reading Go to Section:

Figure 20 -7 The Life Cycle of Plasmodium Section 20 -2 Go to Section:

Zooflagellates • • • Cell Type: Unicellular, eukaryotic Mode of Nutrition: Heterotrophic Movement: flagella Where they live: water and fluid environments Reproduction: Asexual Examples: – Trypanosoma – Causes African Sleeping Sickness, – Trichonympha – found indigestive system of termites Go to Section:

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Plant- like protists • Cell Type: some unicellular, some multicellular (algae), eukaryotic • Mode of Nutrition: AUTOTROPHIC contains chlorophyll to carry out photosynthesis. Some can be heterotrophic when light is not present • Movement: some have flagella, some have cilia • Where they live: aquatic environments, soil, some live in colonies • Reproduction: mainly asexual, but some sexual (alternation of generations, spores) Go to Section:

Types of Plant Like Protists • Algae- are at the base of aquatic food chains (3 types- green, brown, and red) • Euglenoids • Dinoflagellates • Diatoms Examples: volvox, spirogyra (spiral shaped chloroplast), euglena Go to Section:

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Interesting Facts About Plant Like Protists • They produce much of the oxygen in aquatic environments • Algae are protist not plants! Just because its green doesn’t mean that it’s a plant. • Some plant like protists are found in toothpastes, pudding, salad dressing that are used as thickeners. Go to Section:

Video Algae • Click the image to play the video segment.

Euglena Section 20 -3 Chloroplast Carbohydrate storage bodies Gullet Pellicle Flagella Go to Section: Eyespot Nucleus Contractile vacuole

2 Flagella No Cell Wall Red Eye Spot to detect light Contains chloplas to carry out photosynthesis Autotrophs and Heterotrophs when sun is not available • Pellicle: stiff outer membrane • • • Go to Section:

• 2 Flagella • No Cell Wall • Red Eye Spot to detect light • Autotrophs and Heterotrophs when sun is not available • Pellicle: stiff outer membrane Go to Section: Pellicle Eyespot

Important euglena structures • Pellicle- stiff outer membrane • Contractile vacuoleregulates and pumps excess water and wastes • Chloroplast- site of photosynthetic activity • Flagella- movement • Eyespot- helps to detect the light • Nucleus- hereditary, genetic material Go to Section:

Fungus-like Protists Cell Type: eukaryotic, unicellular majority of time Mode of Nutrition: heterotrophic, decomposers Reproduction: asexual and sexual stages by spores Where they live: water or moist environments, decaying plants and trees • Movement: can all move at some point, some have pseudopods (slime mold) • Commonly called: slime molds and water molds. Water molds responsible for the Irish Great Potato Famine, can destroy crops • Examples: Acrasiomycota - Cellular Slime Mold, Myxomycota - Acellular Slime Mold, Oomycetes- Water mold • • Go to Section:

• Water Mold And slime mold Go to Section:

Go Online • Links on funguslike protists • Interactive test • Articles on protists • Articles on protozoans • For links on protists, go to www. scilinks. org and enter the Web Code as follows: cbn-6201. • For links on algae, go to www. scilinks. org and enter the Web Code as follows: cbn-6204.