Lecture 17: Fungi I Flashcards
The drug penicillin comes from which microorganism?
The mold Penicillium
How many fungal species have been described to date?
100,000
How many new fungal species are discovered every year?
1,700
What percentage of fungal species have been identified?
<7%
Name the 6 major characteristics of fungi.
- Eukaryotic
- Chitin cell walls
- Reproduction by spore formation
- Unicellular (round yeast cells) and multicellular structures (hyphae)
- Heterotrophic
- Mostly nonmotile
What is the most common form of spore dissemination?
WInd
What is the thallus?
The fungal body - a large single cell
What are hyphae?
They are filamentous tubular structures with internal septa (sometimes) and multiple nuclei
What are the two types of hyphae (in terms of structure)?
Septate hyphae: have cross-walls, which allow the cytoplasm to flow through
Coenocytic hyphae: do not contain septa
What is mycelium?
It is a group/mass of hyphae, often used interchangeably with hyphae.
What are the two types of hyphae (in terms of function)?
Vegetative hyphae: obtain nutrients
Aerial hyphae: involved in reproduction
Hyphae that extend above the surface produce […] called […]
Spores called conidia
Describe two characteristics of conidia spores.
They are pigmented and resistant to drying.
Describe the reproductive cycle of conidia.
Reproduction is asexual. The conidia (spores) fly off and germinate. They eventually land elsewhere and grow a new hyphae, which then grow new conidia.
What are the three types of fungal morphology?
Yeast, mold, or dimorphic
Describe yeast morphology.
It is non-filamentous, unicellular fungi that are typically oval or spherical
What are the two types of yeast? Explain the difference between them.
Fission yeast: divide evenly to produce two new cells
Budding yeasts: divide unevenly, yielding a bud smaller than the parental cell