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Characteristics 2

Non photosynthetic Non chlorophyllous  Eukaryotes  Non motile  Most are saprobes (live on dead organisms) 3

 Absorptive heterotrophs (digest food first & then absorb it into their bodies  Release digestive enzymes to break down organic material or their host  Store food energy as glycogen BREAD MOLD 4

 Important decomposers  Most are multicellular, except unicellular yeast  Lack true roots, stems or leaves MULTICELLULAR MUSHROOM UNICELLULAR YEAST 5

 Cell walls are made of chitin (complex polysaccharide)  Body is called the Thallus  Grow as microscopic tubes or filaments called hyphae 6

 Some fungi are internal or external parasites  A few fungi act like predators & capture prey like roundworms Predaceous Fungi feeding on a Nematode (roundworm) 7

 Some are edible, while others are poisonous EDIBLE POISONOUS 8

 Parasites - feeding on living tissue of a host.  Parasites that cause disease are called pathogens. 9 Spore production and dispersal is enormously efficient in fungi and plants of the same species crowded together in fields are ripe for attack. Fungal diseases can on occasion result in the loss of entire crops if they are not treated with antifungal agents.

 Produce both sexual and asexual spores  Classified by their sexual reproductive structures Spores come in various shapes 10

 Grow best in warm, moist environments  Mycology is the study of fungi  Mycologists study fungi  A fungicide is a chemical used to kill fungi Fungicide kills leaf fungus 11

 Fungi include puffballs, yeasts, mushrooms, toadstools, rusts, smuts, ringworm, and molds  The antibiotic penicillin is made by the Penicillium mold Penicillium mold Puffball 12

 Some species of agaricus are commonly cultivated as a food, for example, the button mushroom, Agaricus campestris. 13

 An effort is being made to increase the cultivation of additional species of mushrooms, specialy in Asia.  Some can be grown on waste products. Many have high protein content. 14

 The (carbohydrate) molecule used to store energy in fungi is glycogen. Glycogen is also used to store energy in the muscle and liver cells of animals but plants have a different storage molecule, called starch. molecule 15

 Fungi are achlorophyllous, which means they lack the chlorophyll pigments present in the chloroplasts in plant cells and which are necessary for photosynthesis. Fungi are therefore incapable of photosynthesischloroplastsplant cellsphotosynthesis 16

The Importance of Fungi 17

 Fungi are also important directly as food for humans. Many mushrooms are edible and different species are cultivated for sale worldwide.  While this is a very small proportion of the actual food that we eat, fungi are also widely used in the production of many foods and drinks.  These include cheeses, beer and wine, bread, some cakes, and some soya bean products. 18

 Penicillin, perhaps the most famous of all antibiotic drugs, is derived from a common fungus called Penicillium.  Many other fungi also produce antibiotic substances, which are now widely used to control diseases in human and animal populations.  The discovery of antibiotics revolutionized health care worldwide. 19

 They maintain the soil fertility by decomposing the dead organic matter.  E.g  Mycorrhizal Fungi 20

 The fungi which make our bread and jam go mouldy are only recycling organic matter, even though in this case, we would prefer that it didn't happen! Fungal damage can be responsible for large losses of stored food, particularly food which contains any moisture 21

 Fungi cause a number of diseases in human beings like aspergillosis (ear, lungs diseases) moniliases (skin, mouth, gums diseases) 22

 Spore production and dispersal is enormously efficient in fungi and plants of the same species crowded together in fields are ripe for attack. 23

Vegetative Structures 24

25 Hyphae can grow and form a network called a mycelium. When a mycelium reaches a certain size (the size depends on the species of the fungus), it begins to form structures called sporangia whose function is to release spores

 Tubular  Tubular shape  ONE  ONE continuous cell cytoplasm & nuclei  Filled with cytoplasm & nuclei  Multinucleate chitin  Hard cell wall of chitin also in insect exoskeletons 26

 Stolons  Stolons – horizontal hyphae that connect groups of hyphae to each other  Rhizoids  Rhizoids – rootlike parts of hyphae that anchor the fungus 27 STOLON RHIZOIDS

 Cross-walls called SEPTA may form compartments  Septa have pores for movement of cytoplasm  Form network called mycelia that run through the thallus (body) 28

 Fungi get carbon from organic sources  Tips of Hyphae release enzymes  Enzymatic breakdown of substrate  Products diffuse back into hyphae Digested material is then used by the hypha Nucleus “directs” the digestive process

 Fungi may be classified based on cell division (with or without cytokinesis)  Aseptate or coenocytic (without septa)  Septate (with septa) 30 NO CROSS WALLS CROSS WALLS

31 HAUSTORIA – parasitic hyphae on plants & animals Septate Hyphae Coenocytic Hyphae

 Hyphae grow from their tips  Mycelium is an extensive, feeding web of hyphae  Mycelia are the ecologically active bodies of fungi This wall is rigidOnly the tip wall is plastic and stretches 32

REPRODUCTIVE STRUCTURES 33

Asexually Sexually  Most fungi reproduce Asexually and Sexually by spores most common genetically identical  ASEXUAL reproduction is most common method & produces genetically identical organisms conditions are poor & nutrients scarce  Fungi reproduce SEXUALLY when conditions are poor & nutrients scarce 34

adaptation  Spores are an adaptation to life on land species will disperse to new locations  Ensure that the species will disperse to new locations reproductive cell  Each spore contains a reproductive cell that forms a new organism  Nonmotile wind  Dispersed by wind 35

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 Used when environmental conditions are poor (lack of nutrients, space, moisture…)  No male or female fungi  Some fungi show dimorphism  May grow as MYCELIA or a YEAST –LIKE state (Filament at 25 o C & Round at 37 o C) 37 Dimorphic Fungi

1n hyphae 2 mating types (+ and -) FUSE (Fertilization)  Haploid 1n hyphae from 2 mating types (+ and -) FUSE (Fertilization)  Forms a hyphae with 2 nuclei that becomes a ZYGOTE  The zygote divides to make a SPORE SPORE FORMS

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 Fragmentation  Fragmentation – part of the mycelium becomes separated & begins a life of its own  Budding  Budding – a small cell forms & gets pinched off as it grows to full size  Used by yeasts  Asexual spores – production of spores by a single mycelium 40

 Spores may be Formed:  Directly on hyphae  Inside sporangia  On Fruiting bodies Amanita fruiting body Pilobolus sporangia Penicillium hyphae

 Fruiting Bodies asexual  Fruiting Bodies are modified hyphae that make asexual spores Sporangiosphore Sporangium  An upright stalk called the Sporangiosphore supports the spore case or Sporangium 42

 Types of Fruiting Bodies:  Basidia  Sporangia  Ascus 43 Basidia Sporangia

mycelium Fruiting Bodies Both are composed of hyphae 44

 Mycelia have a huge surface area  More surface area aids digestion & absorption of food mycelium Germinating spore 45

Evolution of Fungi 46

 Which of the following is most closely related to a mushroom (fungus)?  WHY? Recent DNA-based studies show that fungi are more similar to animals than to plants 47

Evolution of the Fungi

REPRODUCTIVE STRUCTURES and SPORES  Fungi are classified by their REPRODUCTIVE STRUCTURES and SPORES  The reproductive structures are: BASIDIA - BASIDIOMYCOTA  BASIDIA - BASIDIOMYCOTA  SPORANGIA - ZYGOSPORANGIA  ASCUS - ASCOMYCOTA 49

 Spores are made of:  Dehydrated cytoplasm  Protective coat  Haploid cell  Wind, animals, water, & insects spread spores  Spores germinates when they land on a moist surface (new hyphae form) 50

Classification & Phylogeny motile spores zygosporangia asci basidia 51

Major Groups of Fungi 52

re-classified into the protists  Within the past few years, several groups have been re-classified into the protists slime molds and water molds  Two of these groups are the slime molds and water molds

 Saprobes  Decomposers  Molds, mushrooms, etc.  Parasites  Harm host  Rusts and smuts (attack plants)  Mutualists  Both benefit  Lichens  Mycorrhizas 54

 Basidiomycota –  Basidiomycota – Club Fungi  Zygomycota –  Zygomycota – Bread Molds  Chytridiomycota –  Chytridiomycota – Chytrids  AM Fungi -  AM Fungi - Mycorrhizas  Ascomycota –  Ascomycota – Sac Fungi  Lichens –  Lichens – Symbiosis (algae & Fungi)

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 Called the sporangium fungi  Commonly called molds  Also includes blights  Hyphae have no cross walls (aseptate)  Grow rapidly  Includes bread mold Rhizopus stolonifer Rhizopus on strawberries Tomato Blight

sporangiumsporangiospores spores  Asexual reproductive structure called sporangium atop sporangiospores make spores  Rhizoids  Rhizoids anchor the mold & release digestive enzymes & absorb food  Stolons  Stolons connect the fruiting bodies Spore production and dispersal is enormously efficient in fungi and plants of the same species crowded together in fields are ripe for attack. Fungal diseases can on occasion result in the loss of entire crops if they are not treated with antifungal agents.

 Sexual conjugation hyphae fuse  Sexual spores are produced by conjugation when (+) hyphae and (-) hyphae fuse ZYGOSPORES  Sexual spores are called ZYGOSPORES endure harsh environments  Zygospores can endure harsh environments until conditions improve zygospore

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 Called Club fungi  Includes:  Mushrooms  Toadstools  Bracket & Shelf fungi  Puffballs  Stinkhorns  Rusts and smuts

(mushrooms)  Some are used as food (mushrooms) (rusts & smuts)  Others damage crops (rusts & smuts) Corn Smut Soybean Rust Portobello Mushrooms

 Seldom  Seldom reproduce asexually fruiting body  The visible mushroom is a fruiting body  Basidiocarp stipe cap Basidia  Basidiocarp (fruiting body) is made of a stalk called the stipe and a flattened cap with gills called Basidia underneath  Basidiospores  Basidiospores are found on basidia  Annulus  Annulus is a skirt-like ring around some stipes  Vegetative  Vegetative structures found below ground 63

Fig Nuclear fusion in basidium Meiosis Hyphal fusion of haploid mycelia haploid mycelium young basidia - the only diploid cells mycelium and fruiting body are dikaryotic N 2N N+N 64

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Sac fungi  Called Sac fungi Cup fungi, morels, truffles, yeasts, mildew  Includes Cup fungi, morels, truffles, yeasts, and mildew (Dutch elm disease and Chestnut blight)  May be plant parasites (Dutch elm disease and Chestnut blight)  Reproduce sexually & asexually  Ascus ascospores  Ascus - sac that makes ascospores in sexual reproduction Ascocarps  Specialized hyphae known as Ascocarps contain the asci

budding  Yeasts reproduce asexually by budding (buds break off to make more yeast cells)  Asexual conidia conidiophores  Asexual spores called conidia form on the tips of special hyphae called conidiophores CONIDIA

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Saccharomyces

 Trufflesmorels  Truffles and morels are good examples of edible ascomycetes  Penicillium mold  Penicillium mold makes the antibiotic penicillin. flavor to cheeses.  Some ascomycetes also gives flavor to certain cheeses.  Saccharomyces cerevesiae  Saccharomyces cerevesiae (yeast) is used to make bread rise and to ferment beer & wine.

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chytrids  Called chytrids motile spores  Produce motile spores saprobes parasites  Mostly saprobes and parasites in aquatic habitats  Biodegrade and recycle  Biodegrade and recycle nutrient s Chytrid that attacks Potatoes

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associated with plant roots  Fungus associated with plant roots  Mutualism  Mutualism between :  Fungus  Fungus (nutrient & water uptake for plant)  Plant  Plant (carbohydrate for fungus) kinds  Several kinds :  Zygomycota – hyphae invade root cells  Ascomycota & Basidiomycota – hyphae invade root but don’t penetrate cells  Extremely important ecologically 74

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 Mutualism between:  Fungus  Fungus (structure)  Algae or cyanobacteria  Algae or cyanobacteria (provides food)  Form a thallus (body)  Foliose  Fruticose  Crustose

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act like sponges  Thalli act like sponges sensitive to pollutants  Some species more sensitive than others to pollutants air quality  Which species are present can indicate air quality pollutants  Most resistant species can also be analyzed for pollutants 78

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