Micro Lecture chapter 12 Fungi

Mycology meaning

The study of fungi

All fungi are

• Chemoheterotrophs

• Decompose organic matter

• Aerobic or facultative aerobic

Chemoheterotroph definition

organism that gets its energy from chemicals and needs to consume others in order to live

falcultative anaerobic definition

Can survive with or w/o the presence of O2

Structures of molds and fleshy fungi

• thallus consisting of

• Septate hyphae

• Coencocytic hyphae

Definition of Thallus

Body

Hyphae definition

filaments

Many filaments or a mass of hyphae are referred to as

mycelium

septate or septa hyphae (Think septum)

Hyphae that contain cross-walls or segments throughout the structure

Coenocytic hyphae (Think coexist)

No walls of separation in the hyphae

Vegetative Hyphae Vs Aerial Hyphae

Vegetative hyphae below obtain nutrients and responsible for growth

Aerial Hyphae are responsible for reproduction

Yeasts

A category of fungi

Yeast structure

nonfilamentous and unicellular

Budding Yeast

Divide unequally

Fission Yeast ( Look at the top of the F for =)

Divide evenly

Dimorphic fungi

Temperature determines if it is a yeast or mold

Yeastlike at 37C (98.6 F) and moldlike at 25C (77F)

Asexual spores

produced via mitosis and cell division

formed by the hyphae of the organism

How do fungi reproduce

formation of spores detach and grow in a new mold

Produced by mitosis and cell division formed by hyphae of 1 organism

Asexual spores

Types of asexual spores

• Conidiospore

• Sporangiospore

• Chlamydoconidium

• Artroconidia

• Blastoconidia

Conidiospore (think of a dandelion)

Multiple single spores at aerial end of hyphae loose and not encased

Sporangiospore

Asexual spore at the aerial end of hyphae encased in a sac. Breaks free of sac at a certain time

Chlamydoconidium

cell swells up and forms a thick resistant wall, spores develop in the harden hyphal segment inside the filament ( think it clams up)

Arthroconidia

first hyphae develops the septate, then the septate breaks off (think of arthro bone breaking)

Blastoconidia [blast off ]

spores bud off a parent cell

Sexual spores

Fusion of nuclei from 2 opposite mating strands 3 phases

Phases of sexual fungi reproduction

1. Plasmogamy Please

2. Karyogamy Karry

3. Meiosis Me

Haploid donor cell nucleus (+) penetrates recipient cell (-)

Plasmogamy

• and - fuse and form a diploid zygote

karyogamy

diploid nucleus produces a haploid nuclei ( sexual spores)

Meiosis