Mycology

Question 1

what type of micro organisms are fungi?

Answer 1

eukaryotic

Question 2

what is the cytoplasm enclosed within in fungi?

Answer 2

a cell wall

Question 3

what is found within the cell wall of fungi?

Answer 3

chitin

Question 4

how do fungi gain nutrients?

Answer 4

absorption of organic molecules from the immediate surroundings

Question 5

how do fungi reproduce?

Answer 5

sexual (meiosis) and asexual (mitosis) spores

Question 6

what is the most common way that fungi reproduces?

Answer 6

asexual spores

Question 7

what are the 2 main morphological forms of fungi?

Answer 7

moulds and yeasts

Question 8

what is the basic cell unit of moulds?

Answer 8

hypha

Question 9

what is the structure of hyphae?

Answer 9

a cylinder which elongates from the tip and is capable of branching

Question 10

what strengthens the tubular wall?

Answer 10

cross walls (septa)

Question 11

what is a feature of the cross wall which means that nutrients can be shared with the whole organism?

Answer 11

they have a central pore which cytoplasm can stream through

Question 12

what makes hypha acellular?

Answer 12

the central pores in the cross wells

Question 13

what are mycelium?

Answer 13

network of hyphae forming the body of the mould

Question 14

what two layers can mycelium consist of?

Answer 14

submerged vegetative mycelium and aerial mycelium

Question 15

what is found on the aerial mycelium?

Answer 15

asexual spores

Question 16

what are yeasts?

Answer 16

an alternative growth form of hypha

Question 17

what do yeasts consist of?

Answer 17

discrete, ovoid cells

Question 18

how does yeast reproduce?

Answer 18

budding

Question 19

what can some yeasts produce?

Answer 19

yeasts and hyphae depending on the environmental conditions

Question 20

what is the name for yeasts which produce both yeasts and hyphae?

Answer 20

dimorphic

Question 21

what is pseudo-mycelium?

Answer 21

intermediate form of growth between hyphae and yeasts in which elongated budding cells form pseudohyphae

Question 22

define colony

Answer 22

in a culture, a mycelium or mass of yeast cells usually grown from a single hyphal fragment or yeast cell

Question 23

what are phylum deuteromycota?

Answer 23

an assemblage of fungi which only produce conidia as there is no sexual reproductive state

Question 24

what group do most pathogenic species fit into?

Answer 24

phylum deuteromycota

Question 25

what are arthrospores?

Answer 25

conidia (spores) formed by simple fragmentation of hyphae in dermatophytes (skin loving bacteria)

Question 26

what does fungi cause as a pathogen?

Answer 26

mycosis (infection) allergy (inhaled spores) toxicosis (usually mycotoxicosis)

Question 27

what are the 2 sources of infection?

Answer 27

endogenous and exogenous

Question 28

where does endogenous infection come from?

Answer 28

commensal flora

Question 29

where does exogenous infection come from?

Answer 29

free living saprophytes in the environment or parasites on another animal host

Question 30

what are the 3 types of infection?

Answer 30

superficial mycoses sub-cutaneous mycoses deep mycoses

Question 31

where are superficial mycoses found?

Answer 31

epidermis

Question 32

where are deep mycoses found?

Answer 32

within the body

Question 33

what can sub-cutaneous mycoses be caused by?

Answer 33

introduction through trauma in the skin

Question 34

what can ringworm cause in cattle?

Answer 34

loss of growth rate lower milk yield scarring which affects hide value contamination will persist for years

Question 35

what are the two ways that fungal infection must be treated?

Answer 35

topically and systemically

Question 36

what stops spores from continuing to reinfect the animal from the environment?

Answer 36

radical approach including thorough cleaning and burning/disposal of animal bedding etc

Question 37

at what temperature do deep mycoses grow best?

Answer 37

blood temperature

Question 38

are deep mycoses contagious?

Answer 38

no

Question 39

when do deep mycoses continue to arise?

Answer 39

when the immune system is compromised or commensals are reduced as they are opportunistic

Question 40

what can cause predisposition to fungal infection?

Answer 40

immune suppression (natural or induced) age trauma exposure to heavy spore loads

Question 41

what are the 3 types of deep mycoses caused by mould?

Answer 41

aspergillosis Mucoromycosis mycotic abortion

Question 42

what are the 2 types of deep mycoses caused by yeast?

Answer 42

candidosis | cryptococcosis

Question 43

what is the main source of aspergillosis?

Answer 43

hay/straw

Question 44

what size are aspergillosis spores?

Answer 44

2-3 micro metres

Question 45

what are the 2 types of aspergillosis?

Answer 45

acute and chronic

Question 46

when is acute aspergillosis seen?

Answer 46

neonates

Question 47

what is a key way of diagnosing chronic aspergillosis in dogs?

Answer 47

uni/bilateral depigmentation of the nose and discharge

Question 48

what does bovine mycotic abortion result in?

Answer 48

infection of placenta and foetus

Question 49

how does bovine mycotic abortion present?

Answer 49

thickened cotyledons, amnion and foetal skin

Question 50

is bovine mycotic abortion contagious?

Answer 50

no

Question 51

where are hyphae found in bovine mycotic abortion?

Answer 51

in tissues and in foetal stomach contents

Question 52

where can the most reliable culture of bovine mycotic abortion be taken from?

Answer 52

foetal stomach contents

Question 53

what are the 2 main types of yeast infections?

Answer 53

candidosis and cryptococcosis

Question 54

where is candidosis often found?

Answer 54

normal gut flora

Question 55

where is cryptococcosis found?

Answer 55

in bird/bat faeces

Question 56

what does cryptococcosis cause?

Answer 56

nasal granuloma, skin ulcers, brain infection

Question 57

when do most fungal infections arise?

Answer 57

during immunosuppression

Question 58

can cryptococcosis be identified by the body?

Answer 58

no as it is surrounded by a capsule

Question 59

what is the most dangerous element of cryptococcosis?

Answer 59

it can be dormant for a number of years and is walled off by the body where it will continue to grow until it bursts

Question 60

what is key when cryptococcosis is being treated?

Answer 60

it is kept moist as the spores can't be shed so easily

Question 61

how can fungal infection be diagnosed normally?

Answer 61

from a skin scrape: direct microscopy, culture and visual ID

Question 62

how can deep mycosis be diagnosed?

Answer 62

serology: checking for antibodies and antigens (e.g. chitin), presence of alcohol and molecular identification using PCR