Fungi and Disease

Question 1

are fungi prokaryotic or eukaryotic

Answer 1

eukaryotic

Question 2

fungi are saprophytic chemoheterotrophs, what does this mean

Answer 2

they absorb nutrients from environment, typically from decaying materials where there is moisture and sugars/starches

Question 3

how might you distinguish a fungus from a bacteria/plant cell

Answer 3

they have a distinct cell wall

Question 4

what are the three categories of fungi morphology

Answer 4

yeast, mould (filamentous- grows hyphae which can have multiple nuclei), and dimorphic (can be single or multi cellular)

Question 5

draw a diagram of aspergillus spp.

Answer 5

labels = besicle, conidia, phialides, conidiophore, hyphae

Question 6

what is the fungal cell wall made of

Answer 6

beta glycans, chitin

Question 7

how are fungi used in society

Answer 7

antibiotics, steroids, enzymes, citric acid

Question 8

how did pythophthora infestans cause the potato blight?

Answer 8

the fungi released spores which infected leaves of potato plants which caused lesions to develop. the disease spread to the tubers which in turn infected the seedlings that arose from said tubers

Question 9

write a note on dermatophytoses

Answer 9

also referred to as tinea or ringworm, this is a superficial mycosis as it affects the skin hair and nails. such fungi that cause these diseases are trichtophyton, microsporum, epidermophyton.

the scalp (dandruff) may also be affected by a yeast malassezia sp

Question 10

write a note on sporotrichosis infection

Answer 10

is a subcutaneous mycosis caused by sporothrix schenkii. this fungus is dimorphic, and resides in the bark of trees/shrubs/plants. it enters the body through cuts in the skin, and its infection spreads along the lymphatics

Question 11

write a note on candidiasis

Answer 11

is an opportunistic infection caused by the fungus candida spp. affects the mouth, GIT, vagina.
Oral candidiasis (thrush) affects infants and immunocompromised individuals
Cutaneous candidiasis (nappy rash) grows in moist warm areas and may also affect nails
Female genital candidiasis (vaginal thrush) resembles the oral disease. may have irritation, ithcing and white discharge

Question 12

write a note on crytococcus neoformans

Answer 12

yeast found worldwide which typically infects the respiratory tract. presents as meningitis in immunocompromised people (t-cell deficient (HIV-AIDS))

Question 13

describe pulmonary aspergillosis

Answer 13

can occur as an infection with pneumonia that spreads to heart lungs brain and kidneys via the bloodstream

Question 13

write a note on aspergillus fumigatus

Answer 13

spore forming mould, ubiquitous and is opportunistic. infection via inhalation of spores resulting in pulmonary disease but can also infect wounds or burns.

Question 14

describe aspergilloma

Answer 14

a fungus ball that colonises in a healed lung scar or abscess from a prior disease

Question 15

write a note on histoplasmosis

Answer 15

ohio, mississippi, mexico. inhaltation of microconidia from bird/bat droppings in the soil. causes acute pulmonary infection, CNS infection, eye infection

Question 16

write a note on coccidioidomycosis

Answer 16

california, arizona, mexico, south america. inhalation of arthroconidia from soil. pneumonia/rash/arthralgia/cavities/meningitis

Question 17

write a note on cryptococcus gattii

Answer 17

spreading since 1999 from vancouver . tree associated with c. neoformans also present