Mycology

Question 1

multicellular fungi are called ____

Answer 1

molds

Question 2

unicellular fungi are called ____

Answer 2

yeasts

Question 3

fungal characteristics

Answer 3

• eukaryotes (have nucleus)
• simple plants
• decomposers
• sexual/asexual reproduction

Question 4

how do spores reproduce?

Answer 4

sexually (meet w other spores)

Question 5

how do conidia reproduce?

Answer 5

asexually (land on any surface)

Question 6

hyphae

Answer 6

tube (hair)-like extensions of cytoplasm

Question 7

mycelium

Answer 7

fungal “mat” consisting of intertwined hyphae
(AKA mushrooms)

Question 8

name 3 ways that hyphae can grow?

Answer 8

• septate hypha (walls)
• coenocytic hypha (no walls between)
• growth of hypha from a spore

Question 9

aerial hyphae grow ____

Answer 9

upward

Question 10

vegetative hyphae grow ____

Answer 10

flat/straight across

Question 11

thermal dimorphism

Answer 11

ability possessed by a fungus to grow as a yeast or as a mold depending on temperature

Question 12

what temperature does yeast grow at?

Answer 12

35-37*C (body temp)

Question 13

what temperature does mold grow at?

Answer 13

22*C (room temp)

Question 14

yeast is a ____ fungus that reproduces ____ via ____

Answer 14

unicellular
asexually
budding (push cytoplasm into wall)

Question 15

fungi reproduce via the formation of ____ that detach from the parent and germinate into a new mold

Answer 15

spores

Question 16

asexual spores are produced via ____, and are formed by…

Answer 16

• mitosis & cell division
• hyphae of one organism

Question 17

conidiospore

Answer 17

not enclosed in a sac

Question 18

arthroconidia

Answer 18

fragmentation of septate hyphae

Question 19

blastoconidia

Answer 19

buds of the parent cell

Question 20

chlamydoconidium

Answer 20

thick-walled cells/spore within a hyphal segment

Question 21

sporangiospore

Answer 21

enclosed in a sac (within a sporangium)

Question 22

conidia are arranged in ____

Answer 22

chains

Question 23

how are sexual spores formed?

Answer 23

fusion of nuclei from 2 opposite mating strains

Question 24

3 phases of sexual reproduction

Answer 24

• plasmogamy
• karyogamy
• meiosis

Question 25

plasmogamy

Answer 25

haploid donor cell nucleus (+) penetrates cytoplasm of recipient cell (-)

Question 26

karyogamy

Answer 26

+ and - nuclei fuse and form diploid zygote

Question 27

meiosis

Answer 27

diploid nucleus produces haploid nuclei (sexual spores)

Question 28

nutritional adaptations of fungi

Answer 28

• grow better at pH of 5
• grow in high sugar and salt concentration; resistant to osmotic pressure
• can grow in low moisture content
• can metabolize complex carbs

Question 29

mycosis

Answer 29

any disease caused by a fungus (yeast or mold)

Question 30

examples of superficial mycoses

Answer 30

• tinea capitis (scalp & eyebrows)
• pityriasis (yeast dermatitis of chest & back)

Question 31

examples of cutaneous and mucocutaneous mycoses

Answer 31

• ringworm
• candidiasis

Question 32

examples of subcutaneous mycoses

Answer 32

• sporotrichosis (puncture contamination)
• zygomatic rhinitis

Question 33

examples of deep mycoses

Answer 33

• coccidiomycosis (valley fever)
• histoplasmosis

Question 34

what type of clothing causes yeast pityriasis?

Answer 34

wick-wear (‘breathable’) -> yeast remains in clothing

Question 35

tinea cruris is also called ____

Answer 35

jock itch

Question 36

what is tinea cruris?

Answer 36

red scaling plaques on medial thighs and inguinal folds

Question 37

tinea cruris may be spread from ____

Answer 37

tinea pedis (athlete’s foot)

Question 38

what is the most common dermatophyte?

Answer 38

tinea pedis

Question 39

etiology of tinea pedis

Answer 39

use of occlusive footwear, presents with toe-web maceration (mold)

Question 40

what is tinea unguium (onychomycosis)?

Answer 40

fungal infection of the nails of either feet or hands

Question 41

what is tinea capitis?

Answer 41

superficial fungal infection of the skin of scalp, eyebrows, and eyelashes, with a propensity for attacking hair shafts and follicles

Question 42

sporotrichosis is also known as ____

Answer 42

rose gardener’s disease or rose gardener’s thumb

Question 43

what causes sporotrichosis?

Answer 43

sporothrix
(fungus throughout the world in soil and on plant matter such as sphagnum moss, rose bushes, and hay)

Question 44

where does histoplasmosis fungus live?

Answer 44

• soil containing large amounts of bird or bat droppings
• in US: central and eastern states, especially around Ohio and Mississippi river valleys
• parts of central & south america, africa, asia, australia

Question 45

do fungal pathogens require a host to complete their life cycle?

Answer 45

no, most do not

Question 46

true fungal pathogens are distributed in a predictable geographic pattern based on ____ and ____

Answer 46

climate and soil

Question 47

valley fever (coccidiodomycosis) can spread beyond the lungs to the bloodstream, and eventually the brain, causing ____

Answer 47

meningitis

Question 48

fungal virulence factors

Answer 48

• thermal dimorphism
• toxin production
• capsules
• adhesion factors
• hydrolytic enzymes

Question 49

name 4 examples of mycotoxins

Answer 49

• aflatoxin
• ergot
• psilocybin
• a-amanitin

Question 50

aflatoxin

Answer 50

• carcinogenic
• found on improperly stored peanuts

Question 51

ergot

Answer 51

• hallucinogen
• alkaloid toxin that affects dopamine
• found on improperly stored grain

Question 52

psilocybin

Answer 52

• hallucinogen (magic mushrooms)
• affects cerebrum and sensory processing
• found in genus Basidiomycota

Question 53

a-amanitin

Answer 53

(death cap mushroom)
- lethal to hepatocytes
- death occurs within 6hrs of ingestion

Question 54

“sick building” syndrome

Answer 54

• caused by toxin production by Stachybotrys chartarum
• severe hematologic and neurologic damage
• water infiltration of building supplies or flood damage