(2) Chapter 12: Mycology Pt.2

What type of hyphae do Zygomycetes have?

Coenocytic hyphae.

What is the common name for Zygomycetes?

Conjugation fungi.

What is the sexual spore of Zygomycetes?

Zygospore.

What is the asexual spore of Zygomycetes?

Sporangiospore.

What structure contains sporangiospores?

Sporangium.

What is a sporangiophore?

The aerial hypha that supports the sporangium.

How are zygospores formed?

Fusion of nuclei from opposite mating types during sexual reproduction.

What process produces zygospores?

Sexual reproduction.

What process produces sporangiospores?

Asexual reproduction.

What happens when a sporangium matures?

It bursts and releases sporangiospores.

What happens after a sporangiospore is released?

It germinates into a new hypha.

What is the vegetative mycelium?

The nutrient-absorbing network of hyphae.

Which two genera are examples of Zygomycetes?

Rhizopus and Mucor.

Which Zygomycetes are important human pathogens?

Rhizopus species and Mucor species.

What makes Microsporidia unique among fungi?

They lack mitochondria.

Do Microsporidia produce hyphae?

No.

What diseases are associated with Microsporidia?

Keratoconjunctivitis and diarrhea.

How are Microsporidia transmitted?

By ingestion or inhalation of spores.

How do Microsporidia infect host cells?

The spore injects its contents into the host cell using a polar tube.

What type of hyphae do Ascomycetes possess?

Septate hyphae.

What is the common name for Ascomycetes?

Sac fungi.

Why are they called sac fungi?

Their sexual spores develop inside sac-like asci.

What is the sexual spore of Ascomycetes?

Ascospore.

What is the asexual spore of Ascomycetes?

Conidiospore (conidium).

Where are ascospores produced?

Inside an ascus.

Where are conidia produced?

On conidiophores.

What structure supports conidia?

Conidiophore.

What process produces ascospores?

Sexual reproduction.

What process produces conidia?

Asexual reproduction.

Give four medically important Ascomycetes.

Aspergillus, Blastomyces dermatitidis, Histoplasma capsulatum, and Microsporum.

What type of hyphae do Basidiomycetes have?

Septate hyphae.

What is the common name for Basidiomycetes?

Club fungi.

Why are Basidiomycetes called club fungi?

Their sexual spores form on club-shaped basidia.

What is the sexual spore of Basidiomycetes?

Basidiospore.

What is the asexual spore of Basidiomycetes?

Conidiospore.

Where are basidiospores produced?

On basidia located beneath the mushroom cap.

How many basidiospores are commonly produced on one basidium?

Four.

How do Basidiomycetes commonly reproduce asexually?

Fragmentation.

Which medically important Basidiomycete was discussed?

Cryptococcus neoformans.

What poisonous mushroom genus was mentioned in lecture?

Amanita.

Why is Amanita dangerous?

It produces potent toxins that may be fatal if ingested.

What is the common name of the deadly Amanita mushroom?

Death cap.

What is a lichen?

A symbiotic association between a fungus and an alga or cyanobacterium.

What organisms make up a lichen?

One fungus plus one alga or one cyanobacterium.

What does the alga or cyanobacterium provide in a lichen?

Sugars produced through photosynthesis.

What does the fungus provide in a lichen?

Protection, moisture retention, and structural support.

What is the cortex of a lichen?

The protective outer fungal layer.

What are rhizines?

Root-like fungal structures that anchor the lichen.

What is the function of fungal hyphae within a lichen?

Support the photosynthetic partner and retain moisture.

Why are lichens considered mutualistic?

Both organisms benefit from the relationship.

Why are lichens good indicators of air quality?

They are highly sensitive to air pollution.

What does the presence of lichens indicate about the environment?

Clean, healthy air.

What important indicator is obtained from lichens?

Litmus (erythrolitmin).

What is usnic acid?

An antimicrobial compound produced by lichens.

Where are lichens especially important ecologically?

In Arctic tundra ecosystems where they serve as food for animals.

What fungus is used to make bread?

Saccharomyces cerevisiae.

What fungus is used to make wine?

Saccharomyces cerevisiae.

What biotechnology product is produced using Saccharomyces cerevisiae?

Hepatitis B vaccine.

What enzyme does Trichoderma produce?

Cellulase.

How is cellulase used industrially?

To clarify fruit juices and process fabrics.

Which fungus produces Taxol?

Taxomyces.

What is Taxol used to treat?

Cancer.

Which fungus is used to produce citric acid?

Aspergillus niger.

What food products are made using Aspergillus niger?

Citric acid and soy sauce.

What is aflatoxin?

A carcinogenic toxin produced by certain fungi.

What foods commonly contain aflatoxin?

Peanuts and other nuts contaminated by molds.

Why is aflatoxin medically important?

It can cause mutations and liver cancer.

What are ergot diseases?

Fungal diseases of grains.

What are rusts and smuts?

Fungal diseases that damage corn and wheat crops.

Why are fungal plant diseases economically important?

They destroy crops and reduce agricultural production.

What are mycoses?

Fungal diseases.

How are mycoses classified?

Systemic, subcutaneous, cutaneous, superficial, and opportunistic.

What is a systemic mycosis?

A fungal infection involving multiple organs or tissues.

What is a subcutaneous mycosis?

A fungal infection beneath the skin.

What is a cutaneous mycosis?

A fungal infection involving skin, hair, or nails.

What is a superficial mycosis?

A fungal infection limited to the outer hair shaft or surface tissues.

What is an opportunistic mycosis?

A fungal infection that primarily affects immunocompromised individuals.

Who is at highest risk for opportunistic fungal infections?

AIDS patients, cancer patients, transplant recipients, diabetics, infants, and the elderly.