Kingdom: FUNGIChapter 19

UNIT 4 – Part 2: Protist & Fungi

FUNGI: Characteristics

• Eukaryotic HETEROTROPHS– External Digestion: secrete digestive enzymes

then absorb food paritcles– SAPROPHYTES: obtain food from dead organisms– PARASITES: obtain food from living organisms

• No roots, stems, or leaves• All are MULTICELLULAR

– Except for YEAST (unicellular)

FUNGI: Structure

• HYPHAE: tiny filaments that make up multicellular fungi– Increases surface area (absorption)

• MYCELIUM: tangled mass of hyphae– Fungal Body (below ground)– Fruiting Body (reproductive structure)

• EX: Mushroom; Fruiting body is what we see

• CELL WALLS: Chitin in cell walls (chitin is found exoskeletons of insects)

FRUITING BODY

MYCELIUM

HYPHAE

HYPHAE

FUNGI: Reproduction… most are BOTH asexual & sexual

• SPORES are found in almost every environment..– But must be in right conditions to grow (warm, most, &

nutrients)

• ASEXUAL – Cells or Hyphae break off and grow on own– Produce Spores which scatter and grow

• SPORANGOIPHORE: specialized hyphae• SPORANGIA: produce spores, top of sporangoiphore

• SEXUAL– Two Mating Types ( + and - )– GAMETANGIUM: opposite types join, produce gametes,

fuse and form zygote; meiosis takes place

GREEN: Sporangiophores ORANGE: Sporangia

BLUE: Spores

FUNGI: Classification

• Classified by Reproduction and Structure of Hyphae

• Four Phylum– Zygomycota– Ascomycota– Basidiomycota– Deuteromycota

Zygomycota & Ascomycota

• COMMON MOLDS (Zygomycota)– EX: Black Bread Mold (Rhizpus stolonifer)

• Dark fuzz that grows on bread in warm moist environments…

• RHIZOIDS (hyphae that anchor & digest bread)• STOLONS (stem like that stretch across bread)• SPORANGIOPHORES (form spores)

• SAC FUNGI (Ascomycota)– EX: Cup Fungi & Yeast

• Yeast are the only unicellular fungi; reproduce asexually by budding (forming asci or sac w/ spores)

BLACK BREAD MOLD

CUP FUNGI

LIFE CYCLE: Bread Mold

Importances of Yeast

Baking and Brewing• Saccharomyces “sugar fungi”• Nutrient rich environment w/out oxygen• Alcoholic FERMENTATION to obtain energy• Products:

– Carbon Dioxide (beverages bubble and bread rise)

– Alcohol (in bread evaporates and remains in beverages)

Basidiomycota & Deuteromycota• CLUB FUNGI (Basidiomycota)

– EX: Mushrooms (Puffballs & Rusts)• CAP (fruiting body), GILLS (spore bearing structure on

cap), STALK, & BASE

– IMPORTANCES…• Mushrooms - commercial crops & decomposers… many

are also poisonous, some hallucinogenic • Rusts & Smuts – plant parasites (corn smut)

• IMPERFECT FUNGI (Deuteromycota)– EX: Penicillim notatum…

• Mold that grows on fruit… Source of antibiotic Penicillin

– Have never observed sexual phase of life cycle… therefore placed in own phylum

SHELF FUNGI “DEATH CAP”Most poisonous

PENICILLIUM

CORN SMUT

Ecological Impact• DECOMPOSERS

– Recycle nutrients; break down dead organisms

• DISEASES: Plants– 15% crop loss in temperate regions (50% in tropical)

• DISEASES: Humans– ATHLETE’S FOOT and RINGWORM: mycelium

infects outer layer of skin; easily spread– VAGINAL YEAST INFECTION and THRUSH:

Yeast grows naturally in most regions of body but kept under control by bacteria and immune system

• Caused by antibiotic or weak immune system