Protists - a member of a group of eukaryotic organisms, which have a membrane bound nucleus.

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1 7ch8 Protists

2 Protists - a member of a group of eukaryotic organisms, which have a membrane bound nucleus. protists are a diverse group with many different adaptations share some characteristics with plants, animals, fungi

3 Reproduction Most reproduce asexually - exact copy of the parent Some reproduce sexually - genetically different from the parent

4 Classification A protist is any eukaryote that cannot be classified as a plant, an animal, or a fungus. Protists are classified as plantlike, animal-like, or funguslike

5 Plantlike Protists Diatoms - microscopic plantlike protist with a hard outer wall very common, diatoms look like colored glass - their cell walls contain silica

6 Plantlike Protists Dinoflagellates - protists with a flagella so it can move around, some glow in the dark

7 Plantlike Protists Euglenoids - instead of a cell wall, they have a rubbery cell coat, a flagellum, eyespots that detect light, and chloroplasts to make their own food prey for tadpoles and small fish

8 Plantlike Protists Algae are plantlike protists that produce food through photosynthesis using light energy and carbon dioxide. Some are large and multicellular, most are small, unicellular

9 Algae Classified as Red, Green, or Brown Red and brown appear similar to plants, have holdfasts to attach to rocks instead of roots do not have a complex system for water transport like plants

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13 Green Algae Volvox - many volvox cells come together to form a large sphere and function as a group

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16 Importance of Algae Ingredient of foods like ice cream, pudding, marshmallows Important in the ecosystem - provide food and shelter - remove pollution from water Problems in ecosystem - can overpopulate and produce wastes that poison other organisms often called a red tide algal bloom

17 Animal-like Protists Protozoans - protists that resemble tiny animals do not have chloroplasts microscopic and unicellular most live in wet environments

18 Ciliates Cilia - short, hairlike structures that grow on the surface of some protists Paramecium - protist with cilia and two types of nuclei

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20 Flagellates uses flagella to move eat decaying matter many live in the digestive of animals

21 Sarcodines Animal-like protists with no specific shape Amoeba - common, with an adaption for movement Pseudopod - a temporary foot that forms as the organism pushes part of its body outward.

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23 Sarcodines get nutrients and energy by: ingesting other organisms make their own food live in the digestive system of humans

24 Importance of Protozoans Decompose dead plant and animal matter Cause disease as parasites Example: malaria p. 272

25 Funguslike Protists Slime and Water Molds Slime molds - cell material floating in a slimy mass - absorb nutrients from other organic matter Water mold - feeds on dead organisms or as a parasite - often causes diseases in plants

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28 Importance of Funguslike Protists Decompose dead organic matter Many attack and consume living plants Example: Great Irish Potato Famine in 1845 destroyed over half of the potato crop

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30 Lesson 2 Fungi World s largest organism Eukaryotes 1.5 million species heterotrophs - cannot make their own food decompose organic matter by dissolving it with chemicals some are parasites

31 Hyphae - threadlike structures usually underground that absorb minerals and water Mycelium - a network of hyphae p. 277

32 Types of Fungi Classified by appearance and type of reproduction structures Can reproduce sexually and asexually Almost all reproduce asexually by spores Spores - small, reproductive cells with a strong outer covering

33 Types of Fungi Club Fungi - named for their various shapes, characteristics Puffballs p.276 Stinkhorns Bird s nest fungus Mushrooms p.278

34 Mushrooms - named for their clublike structure above ground called a basidiocarp. Basidia - reproductive structures inside the basidiocarp that produce sexual spores

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36 Sac Fungi named for their reproductive structures - spores develop on a structure that looks like a sack (ascus) Ascus - structure where spores develop common types: yeast, diaper rash,

37 Zygote Fungi Have stalks called zygosporangia that release spores Example: bread mold, fungi in damp places like a damp basement or a shower curtain

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39 Imperfect Fungi No sexual reproductive stage Examples: athlete s foot blue cheese - the blue color comes from fungi

40 Importance of Fungi Used in the production of many food products Cheese, bread, soda, chocolate, meat substitute Make antibiotics

41 Importance of Fungi - Decomposers Fungi break down organic matter for food By decomposing dead organic matter, they recycle nutrients in the soil Fungi also break down pollution, including pesticides in the soil

42 Fungi and Plant Roots Many plants and fungi grow together The roots of plants and the hyphae of fungi weave together to form a structure called mycorrhiza

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45 Mycorrhiza Exchange molecules: fungi break down decaying matter in the soil and provide some of these nutrients to the plant The plant provides some sugar from photosynthesis to the hyphae of the fungus The hyphae also increase the plant s ability to absorb water page 282

46 Health and Medicine Fungi can make you sick: athlete s foot, rashes, allergies, pneumonia, thrush. Fungi can also be used to make medicine: penicillin The fungus penicillium restricts bacterial growth Page 283

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48 Lichens A structure formed when fungi and certain other photosynthetic organisms grow together. Usually a sac or club fungus that lives together with a green algae or a photosynthetic bacterium. The fungus hyphae grow in a layer around the algae cells

49 Benefits of Lichens Can survive harsh environments - fungus provides water and nutrients, algae can make food from photosynthesis. Food for other organisms Create soil Page 284

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