Intro to fungi

Question 1

Sabrobes

Answer 1

live on dead or decaying, symbionts are association with mutual advantage, commensals is where one benefits and the other is neither harmed nor benefitted and parasites live on or within a host and are harmful to the host.

Question 2

yeasts

Answer 2

unicellular, typically round/oval ASEXUAL repro through budding, pseudohyphae

Question 3

Moulds

Answer 3

multicellular, filamentous/tubular hyphae (septate or aseptate or coenocytic). Sexual or Asexual repro spores.

Question 4

true hyphae

Answer 4

permanence, differentiation, branching, arthrospores and chlamydiospores.

Question 5

Mycelium

Answer 5

intertwined mat of hyphae, vegetative are like the roots and are attached to substrate/penetrate to obtain substrate. Reproductive ae the arial structures (asexual reproduction propagules (conidia

Question 6

Aspergillus sp

Answer 6

always in mycelial phase even in deep tissue infections

Question 7

Torula sp.

Answer 7

exist only as yeast.

Question 8

KOH procedure

Answer 8

take scraping from margin, place on slide add KOh add 1 drop of lactophenol cotton blue so you can get rid of other

Question 9

fungal gram stain

Answer 9

appear gram positive.

Question 10

fungi do not have

Answer 10

structures of locomotion or capsules (except crytpococcus neoformans.

Question 11

fungal cell wall.

Answer 11

no peptidoglycan, aminoglucan Chitin, also had beta glucan

Question 12

cytpolasmic membrane of fungic contains

Answer 12

ergosteral, not cholesterol.

Question 13

4 pathogenic eumycota

Answer 13

zygomycotina, ascomycotina, baidomycotina, deutormycotina.

Question 14

Zygomycotina

Answer 14

most primitive, bread molds, non-septate, reproduce sexually and asexually (sporangium) opportunistic pathogen. examples Rhizopus, Mucor sp. water molds.

Question 15

Ascomycotina

Answer 15

septate, asexual(conidia) sexual spores (ascospores) includes yeasts moulds, dermatophytes, some aspergillus

Question 16

Basidomycotina

Answer 16

septate, produce sexual spores (basidiospores) includes mushrooms and puffballs, filobasidiella neoformans.

Question 17

Deuteromycotina

Answer 17

fungi imperfecti- septate, reproduce asexually, sexual reproductive structures unknown- epidermophyton, microsporium, Tricophyton, Candida.

Question 18

all fungi grow

Answer 18

axenically without others and all are aerobic or facultative and most are not capable of invading living human tissue.

they extend at the tip through apical growth with continuous protoplasm movment into tip. this provides prenetrating power and fresh nutrients. Hyphae–>

Question 19

Free living state

Answer 19

myceliel or hyphal form, at ub phsyiological temperature and there are distinct sexual froms displayed

Question 20

oblitgate aerobes

Answer 20

have catalase ans superoxide dismutase, require 1 atmospher(20%)

Question 21

Microaerophiles

Answer 21

grow in presenceof O2 but only 4% if toxic ROS increase enzyme systems are overloaded and it inhibits growth, has only superoxide dismutase.

Question 22

Obligate anaerobes

Answer 22

lack ROS removing enzymes,

Question 23

factultateve anaerobes

Answer 23

grow in presence or absence of O2; Aerobic respiration, fermentation but best under aerobic conditions ex. Enterobacteriacea has both catalase and superoxid dismutase.

Question 24

fungi(moulds) are normally

Answer 24

aerobic

Question 25

yeasts are normally

Answer 25

facultative anaerobes

Question 26

Aw. for yeasts and bold.

Answer 26

0.60(osmophilic yeasts), for most yeasts .95-.85, for most moulds .7-.8 , for xerophilic moulds .55-.7

Question 27

autotroph

Answer 27

CO2 the sole or principle form of C source

Question 28

Heterotroph

Answer 28

reduced/preformed organic molecules and other organisms.

Question 29

chemotrophs

Answer 29

oxidation(organic or inorganic)

Question 30

Lithotrophs

Answer 30

reduced inorganic moleculs

Question 31

organotrophs

Answer 31

organic molecules

Question 32

most pathogens are

Answer 32

chemoorganotrphoic heterotrophs.

Question 33

all purpose medium

Answer 33

supports growth of most mircoroganisms, has nutrient agar, and broth, trypitcase soy broth

Question 34

enriched media

Answer 34

basal growth support media plus nutritive supplements added(blood agar)

Question 35

reduced medium

Answer 35

addition of reduction agent to remove O2 (cystine, thioglycolate, ascorbate) so that anaerobes can grow.

Question 36

Selective medium

Answer 36

allows one species to grow and suppresses others. you can do this by adjusting pH, specific C or energy source, increase osmotic pressure or adjust O2 tension, (slamonella shigella agar, mannitol salt agar

Question 37

differential meidum

Answer 37

more than one type of organism can grow but serparation is based upon visible changes in the media and distinquishes between various genera.

Question 38

media can be both

Answer 38

selective and differential or enriched and differential

Question 39

fungal cultivation

Answer 39

selective isolation on Sabouraud’s agar using peptone and a pH of 5.6 with antibiotics of penicillin, sterptomycin, tetracycline.

Question 40

corn meal agar

Answer 40

used for culture and species ID, incubated at 25* for several days until sexual structures develop to ID.

Question 41

fungal toxins

Answer 41

A. fumigatus- Gliotoxin that inhibits macrophage phagocytosis, T-cell activation and induces apoptosis. A. flagvus- aflatoxin, carcinogenic