Survey of Mycology Flashcards
New material.
Are Fungi Prokaryotes or Eukaryotes?
Eukaryotes
Examples of unicellular and multicellular fungi.
unicellular: yeast
multicellular: molds, mushrooms
Give 4 facts about fungi.
- Aerobic or facultatively anaerobic.
- Grow at lower pH than bacteria.
- Tolerant of salt and sugar.
- Asexual or sexual reproduction.
What are 4 good functions of fungi?
- Saprophytes: break down dead and decaying materials to decompose.
- Use exoenzymes.
- Food production.
- Antibiotic production.
What do fungal heterotrophs metabolize? 2 Examples?
Metabolize complex carbs (lignin and cellulose).
True or false: some fungi are apart of our normal microbiota
True.
What are the cell walls of fungi made of?
Chitin.
How do yeasts reproduce?
Asexually, by budding.
How do filamentous molds and mushrooms reproduce?
Reproduce with spores (NOT like bacterial spores).
What can yeasts produce? Can all yeasts produce this?
Yeasts can produce hyphae. Not all yeasts can produce this.
What is hyphae?
Tubular, branching filaments of cells.
Multicellular yeasts have what?
Hyphae and mycelium.
How are multicellular yeasts classified?
By their reproductive spores (sexual and asexual types exist).
Systemic pathogens are often what?
Often opportunistic, and are often dimorphic.
What does it mean for fungi to be dimorphic?
They are filamentous mold in the environment, but yeast-like in the host?
How are dimorphic yeast regulated?
By environmental factors.
What is mycoses?
Illness caused by fungal pathogen, some are opportunistic.
Fungal pathogens cause disease by what 3 things?
- Stimulating inappropriate immune responses.
- Toxins
- Acting as carcinogens.
Fungal growth in the body can be what two things?
- Superficial
2. Systemic (often opportunistic)
How are superficial infections of fungi transmitted?
Via direct contact and formites (combs, hats, etc.)
From other animals (cats are most common)
What are two examples of superficial fungal infections?
- ringworm = tineas
2. dandruff
Where do tineas inhabit, and what do they cause?
Tineas inhabit keratinized areas.
They cause an itchy rash.
What is tinea pedis?
Athletes foot.
What is tinea capitis?
Tinea of the scalp, eyebrows, eyelids
What is tinea corporis?
Tinea of the body.
What is tinea unguium?
Tinea of nails.
How is tinea diagnosed?
A sample is placed in KOH to dissolve keratin, or look for spores.
How is tinea treated?
Topical antifungal.
What is dandruff?
Overgrowth of fungi (malassezia), which is normal microbiota. It causes a hyper-turnover of cells.
Sebaceous gland activity is involved.
True or false: bacterial involvement is not likely with dandruff
False. Bacterial involvement (such as staph) is likely.
True or false: genetic susceptibility is likely for dandruff.
True.
How is dandruff treated?
Topical antifungals.
How is candidiasis caused?
Caused by Candida species, which is part of the normal microbiota.
Overgrowth of candida leads to what?
- Thrush (common in mouth and throat)
2. Vaginitis (common)
True or false: systemic infections of candidiasis is rare
True. It is also rarely transmitted from person to person.
Most transmissions of candidiasis is what type?
Aireborne/respiratory.
Most of candida lives where?
In soil.
What 5 things cause systemic predispositions of candidiasis?
- Chronic debilitating diseases.
- Change to metabolism
- Damage to microbiota
- Antibiotics
- Steroids
Candidiasis often resembles what?
TB and cancer.
If candidiasis enters the blood (often through procedures), what can happen?
Endocarditis or pulmonary granuloma.
PRIMARY CAUSE OF FUNGAL DEATH.
True or false: few molds produce toxins that can be inhaled.
False. MANY molds produce toxins that can be inhaled.
High levels of mold can be problematic for those with what 3 things?
- Allergies
- Asthma
- Immunocomproimised
How can we control and limit our exposure to mold?
Reducing indoor moisture levels controls mold.
