Fungi Kingdom

General CharacteristicsGeneral Characteristics

EukaryotesEukaryotes

Cell Wall composed of Cell Wall composed of chitinchitin

HeterotrophsHeterotrophs– Digest then ingestDigest then ingest

Most are decomposersMost are decomposers

Characteristics, cont.Characteristics, cont.

Require moisture to growRequire moisture to grow

Survive drying out bySurvive drying out by– DormancyDormancy– SporesSpores

Less sensitive to osmotic pressure Less sensitive to osmotic pressure than prokaryotesthan prokaryotes

Body PlanBody Plan

Simplest – Simplest – YEASTSYEASTS– UnicellularUnicellular– Round or oval shapeRound or oval shape

Most are filamentous – Most are filamentous – MOLDSMOLDS– long, branched, thread-like filaments long, branched, thread-like filaments

called called hyphaehyphae– Hyphae form tangle mass called Hyphae form tangle mass called myceliummycelium

HYPHAE

Develop from a unicellular spore

Grows from the tip into a food source

Absorbs nutrients through large surface area

Most hyphae are divided by septa

Coenocytic hyphae lack septa

Fungal ReproductionFungal Reproduction

Most reproduce by spores Most reproduce by spores

SporesSpores

Nonmotile reproductive cells Nonmotile reproductive cells dispersed by wind, water, or animalsdispersed by wind, water, or animals

Produced in specialized aerial Produced in specialized aerial hyphae or fruiting bodieshyphae or fruiting bodies

May be produced either sexually or May be produced either sexually or asexuallyasexually

Fungal Life Cycle:Fungal Life Cycle:

Spore lands on suitable Spore lands on suitable food sourcefood source

GerminationGermination

Hyphae grow/elongate Hyphae grow/elongate – Infiltrate food source Infiltrate food source – Forms myceliumForms mycelium

Fruiting body forms – Fruiting body forms – spores producedspores produced

Produced by mitosisProduced by mitosis

Conidiophores – specialized Conidiophores – specialized hyphae that produce asexual hyphae that produce asexual spores called spores called conidiaconidia

Asexual SporesAsexual Spores

Asexual ReproductionAsexual Reproduction

Yeast – primarily by buddingYeast – primarily by budding

Sexual ReproductionSexual Reproduction

Most FungiMost Fungi

Most fungal cells contain haploid Most fungal cells contain haploid nucleusnucleus

Hyphae of 2 compatible mating types Hyphae of 2 compatible mating types come together, cytoplasms fusecome together, cytoplasms fuse– Result is cell with 2 haploid nucleiResult is cell with 2 haploid nuclei

Generalized Sexual Generalized Sexual Reproduction:Reproduction:

Fungal Diversity and Fungal Diversity and ImportanceImportance

SymbiosisSymbiosis

MycorrhizaeMycorrhizae– 80% of plants have fungus growing in or on 80% of plants have fungus growing in or on

rootsroots

– Decompose organic matter in soil – release Decompose organic matter in soil – release nutrientsnutrients

– Increase surface area of rootsIncrease surface area of roots

LichensLichens– Fungus + photoautotrophFungus + photoautotroph

– Important in soil formation from rockImportant in soil formation from rock

– Pollution indicatorPollution indicator

Positive ImpactPositive Impact

Food and food productionFood and food production– Mushrooms & trufflesMushrooms & truffles– Wine, beer through fermentationWine, beer through fermentation– BreadBread– Certain cheesesCertain cheeses

Medicine and ScienceMedicine and Science– Drugs ex. penicillinDrugs ex. penicillin– BiotechBiotech

Negative ImpactNegative Impact

Animals:Animals:– Superficial - Ringworm, athlete’s foot, Superficial - Ringworm, athlete’s foot,

jock itchjock itch– Serious diseases: aspergillosis, Serious diseases: aspergillosis,

histoplasmosishistoplasmosis– Produce toxinsProduce toxins

PlantsPlants– 70% of all major crop diseases70% of all major crop diseases– Rusts, smuts, blight, rotRusts, smuts, blight, rot