FUNGIFUNGI

An OverviewAn Overview

Characteristics of FungiCharacteristics of Fungi

►EukaryoticEukaryotic►Nonphotosynthetic ( heterotrophic)Nonphotosynthetic ( heterotrophic)►Most are multicellularMost are multicellular►Most are microscopic molds or yeastsMost are microscopic molds or yeasts

The study fungi is known as MYCOLOGY.

Structure of FungiStructure of Fungi

► Filaments of fungi Filaments of fungi are called hyphae. are called hyphae.

► The cell walls The cell walls contain chitin.contain chitin.

► The MYCELIUM is a The MYCELIUM is a mat of hyphae mat of hyphae visible to the visible to the unaided eye ( bread unaided eye ( bread mold)mold)

► Some hyphae may Some hyphae may divided by cross divided by cross sections called septasections called septa

SeptatedSeptated

Unseptated - Unseptated - coenocyticcoenocytic

ReproductionReproduction►Most fungi reproduce both sexually Most fungi reproduce both sexually

and asexually.and asexually.►Asexual reproduction – production of Asexual reproduction – production of

various types of sporesvarious types of spores Sporangiophores- upright stalk with an Sporangiophores- upright stalk with an

enclosed sac ( bread mold)enclosed sac ( bread mold) Conidia - upright stalk with no enclosed Conidia - upright stalk with no enclosed

sac (penicillin)sac (penicillin) Fragmentation – hyphae dry out and Fragmentation – hyphae dry out and

shatter releasing individual cells that act shatter releasing individual cells that act like spores (athlete’s foot)like spores (athlete’s foot)

Budding – small offspringBudding – small offspring

►Sexual reproductionSexual reproduction ““plus and minus” mating typesplus and minus” mating types Hyphae of different mating types fuse and Hyphae of different mating types fuse and

give rise to a specialized structure that give rise to a specialized structure that produces spores ( diploid)produces spores ( diploid)

Most fungi are haploid throughout most of Most fungi are haploid throughout most of their life cycletheir life cycle

►When environmental conditions are When environmental conditions are favorable, asexual reproduction occurs favorable, asexual reproduction occurs rapidly. When unfavorable conditions rapidly. When unfavorable conditions stress the organism, sexual stress the organism, sexual reproduction occurs and the offspring reproduction occurs and the offspring have an increased likehood that they have an increased likehood that they will be better suited for the will be better suited for the environment.environment.

Fungi decompose dead plant Fungi decompose dead plant and animal matter.and animal matter.

► Called saprophytes, they act as recyclers of Called saprophytes, they act as recyclers of dead organic matter, obtaining food from dead organic matter, obtaining food from this material. this material.

► Hyphal tips release enzymes that eventually Hyphal tips release enzymes that eventually decompose and release organic materials decompose and release organic materials into the surrounding environment. into the surrounding environment.

► Saprophytic fungi appear on dead trees, Saprophytic fungi appear on dead trees, logs, plant litter such as leaves, and even logs, plant litter such as leaves, and even dead insects and animals. Examples: "Gem-dead insects and animals. Examples: "Gem-studded Puffball" (studded Puffball" (Lycoperdon perlatumLycoperdon perlatum) ) and "Turkey Tail"(and "Turkey Tail"(Trametes versicolorTrametes versicolor). ).

Fungi and HumansFungi and Humans

►Many people have allergies triggered Many people have allergies triggered by mold. by mold.

►Fungal skin infections – skin, nails and Fungal skin infections – skin, nails and hairhair Ringworm, athlete’s footRingworm, athlete’s foot

► Internal organs - HistoplasmosisInternal organs - Histoplasmosis

Fungi in IndustryFungi in Industry

►Fungi produce many products used in Fungi produce many products used in the medical field such as penicillin, the medical field such as penicillin, cephalosporin antibotics, cortisonecephalosporin antibotics, cortisone

►Fungi are used in genetic engineering – Fungi are used in genetic engineering – vaccine for hepatitis B was developed vaccine for hepatitis B was developed using the yeast plasmid as the vector.using the yeast plasmid as the vector.

►Yeast is used to make ethanol.Yeast is used to make ethanol.►Yeast are known for making breads rise.Yeast are known for making breads rise.

Fungi in the Food IndustryFungi in the Food Industry

Mushrooms, morels and truffles are widely consumed by humans.

Fungi are Plant PathogensFungi are Plant Pathogens

► Many fungi attack Many fungi attack grain or fruit.grain or fruit.

Fungi form beneficial Fungi form beneficial partnerships (symbiosis) with partnerships (symbiosis) with other organisms such as trees other organisms such as trees

and flowering plants:and flowering plants:

Lichen – symbiotic relationship between

algae and fungi

AlgaeAlgae

hyphaehyphae

LabLab