Kingdom FungiKingdom Fungi

The Characteristics of FungiThe Characteristics of Fungi• Body form

* unicellular * Multi-cellular

Mycelium – Branched HyphaeMycelium – Branched Hyphae

fruiting bodiesfruiting bodies

both are composed of hyphae

The Characteristics of FungiThe Characteristics of Fungi

• Heterotrophic -* Saprophytes or saprobes –

* Symbionts -

* Parasites –

• Parasites that cause disease are called pathogens.

The Characteristics of FungiThe Characteristics of Fungi

• Heterotrophic - 'other food' * Saprophytes or saprobes - feed on dead

tissues or organic waste (decomposers)* Symbionts - mutually beneficial

relationship between a fungus and another organism

* Parasites - feeding on living tissue of a host.  • Parasites that cause disease are called

pathogens.

Heterotrophic by AbsorptionHeterotrophic by Absorption• Fungi get carbon from organic sources• Hyphae release enzymes• Enzymatic breakdown of substrate• Products diffuse back into hyphae

Product diffuses backinto hypha and is used

Nucleus hangs backand “directs”

HyphaeHyphae

• Tubular• Hard wall of chitin• Grow at tips

Hyphal growthHyphal growth• Hyphae grow from their tips• Mycelium = extensive, feeding web of hyphae

• Mycelia are the ecologically active bodies of fungi

This wall is rigid Only the tip wall is plastic and stretches

Modifications of hyphaeModifications of hyphae

Fungi as Saprobes and Fungi as Saprobes and DecomposersDecomposers

Fungi as Symbionts (Mutualism)Fungi as Symbionts (Mutualism)

LichensLichens• “Mutualism” between

* Fungus – structure* Alga or cyanobacterium –

provides food

Lichen internal structureLichen internal structure

Lobaria

Lichens are nature’s biological indicators of Lichens are nature’s biological indicators of pollution and air quality.pollution and air quality.

Fungi as Parasites & PathogensFungi as Parasites & Pathogens

Fungi are Spore-ific!!!Fungi are Spore-ific!!!

• Spores - asexual (product of mitosis) or sexual (product of meiosis) in origin.

Reproduce by sporesReproduce by spores• Formed:

* Directly on hyphae

Penicillium hyphae with conidia

Hyphal growth from sporeHyphal growth from spore

mycelium

germinatingspore

• Mycelia have a huge surface area

The Characteristics of FungiThe Characteristics of Fungi• Classified by how they reproduce.• 100,000 Species (estimated 1.5 million species

total).• Found everywhere• Cell wall present, composed of cellulose and/or

chitin. • Food storage - generally in the form of lipids and

glycogen. • Eukaryotes - true nucleus and other organelles

present. • All fungi require water and oxygen.

Ascomycota – “sac fungi”Ascomycota – “sac fungi”

• Sexual Reproduction – asci (sing. = ascus) - SAC

• Asex. Reprod. – common• Cup fungi, morels, truffles• Important plant parasites &

saprobes• Yeast - Saccharomyces• Decomposers, pathogens,

and found in most lichensA cluster of asci with spores inside

Sac fungi diversitySac fungi diversity

http://www.youtube.com/watch?v=K9HyPxzNTPY&feature=related

Basidiomycota – “club fungi”Basidiomycota – “club fungi”• Sexual Reproduction – basidia -

CLUB• Asexual reprod – not so

common• Rusts & smuts –plant parasites• Mushrooms, puffballs• Enzymes decompose wood,

leaves, and other organic materials

SEM of basidia and spores

Bioluminescence in Bioluminescence in MycenaMycena

Deuteromycota – Form Phylum Deuteromycota – Form Phylum “Imperfect Fungi”“Imperfect Fungi”

• Fungi that seldom or never reproduce sexually.

• Asexual reproduction by vegetative growth and production of asexual spores common.

YeastsYeasts• Single celled fungi• Adapted to liquids

* Plant saps* Water films* Moist animal tissues

CandidaSaccharomyces

MoldsMolds• Rapidly growth• Asexual spores• Many human importances

* Food spoilage* Food products* Antibiotics, etc.

Noble Rot - Botrytis

HUMAN-FUNGUS INTERACTIONSHUMAN-FUNGUS INTERACTIONS

• Beneficial Effects of Fungi * Decomposition - nutrient and carbon

recycling. * Biosynthetic factories. Can be used

to produce drugs, antibiotics, alcohol, acids, food (e.g., fermented products, mushrooms).

Harmful Effects of Fungi Destruction of food, lumber, paper, and cloth.

Animal and human diseases, including allergies.

Toxins produced by poisonous mushrooms and within food (e.g., grain, cheese, etc.). Plant diseases.