Lecture 7 - Fungal structure and growth

Question 1

what type of metabolism do fungi have

Answer 1

organoheterotroph

Question 2

what type of organism is fungi

Answer 2

eukaryotes
mostly haploid
mostly aerobic

Question 3

how many phyla is fungi divided into

Answer 3

5
they all end in mycota, except microsporidia = this one doesnt exist anymore they changed it to protist

Question 4

what type is chytridomycota

Answer 4

aquatic fungi
they have flagellated spores to help them move in water
and are axexual and sexual

Question 5

what are rhizoids

Answer 5

look like roots
grow out of thallus
helps absorb stuff from surroudnings and have motile zoopores

Question 6

what charcteristic disease to chytridomycota

Answer 6

fatal pandemic disease in amphibians
poor frog

Question 7

what is zygomycota

Answer 7

the bread mold one
terrestrial only
asexual non-motile spores
Also sexual zygospores
some are pathogenic to humans

Question 8

what are conjucated fungi

Answer 8

+ve and -ve versions
means it can sexually reproduce
they fuse to form zygospores the zygospore is sexual - undergoes meiosis to produce haploid spore

Question 9

what are ascomycota

Answer 9

largest group
produce ascospores (8) which are in an ascus = these are sexual

Question 10

what is conidiospore

Answer 10

these are spores released to reproduce asexually

Question 11

what is basidiomycota

Answer 11

club fungi - mushrooms/toadstools
most advanced
m

Question 12

are basidiomycota sexual or asexual

Answer 12

sexual
form 4 basidiospores (- or +)
and these form on basidium (swollen hyphae cells)
these line the gills/pores of the mushroom

Question 13

what kind of association do basidiomycota form with trees

Answer 13

mycorrhizal
they have a mutually beneficial relationship

Question 14

in terms of cell structure, what are the 3 types of structure fungi have

Answer 14

yeasts (unicellular)
filamentous
or
dimorphic (a combo of both)

Question 15

how would a dimorphic fungi turn into unicellular form

Answer 15

temperature dependant
so at 37deg
will turn unicellular

Question 16

effect of yeast form of fungi

Answer 16

can lead to resp infections in humans
e.g. histoplasma

Question 17

how do dimorphic fungi turn into filamentous

Answer 17

at 20-25 deg
allows it to grow and spores to spread in environment

e.g. sporothix
grows in environemnt, but can cause lung infection in its unicellular form

Question 18

what process do yeast use to grow

Answer 18

budding
a form of asexual reproduction
remains attached as it grows
separates only when it is mature
new organism is genetically idential to parent

Question 19

what process do filamentous fungi use to grow

Answer 19

form network of hyphae
these have spores called conidia
these are what spread and germinate

Question 20

what is mycelium

Answer 20

network of fungal threads/hyphae
the conidia are what make this look dusty (green stuff in mold)

Question 21

how do hyphae grow

Answer 21

apical growth
so only grows from the tip
grows outwords to gain more nutrients

Question 22

what is basidiocarp

Answer 22

the fruiting body of the mushroom
spores will form here

Question 23

what is the first stage of formation of fruiting body

Answer 23

hyphal knot

Question 24

what are the 2 types of hyphae

Answer 24

septate - seperated cells, w/ tiny holes allow flow of nutrients
coenocytic - no separation, it’s just a long cell w/ multiple nuclei (more primitave)

Question 25

fungal cell wall structure: what is uppermost layer of fungus

Answer 25

mannoproteins

Question 26

what polysaccharide is in fungal cell walls

Answer 26

beta glucans

Question 27

what is chitin made up of

Answer 27

polymer of beta 1,4 N - acetylglucosamine
forms microfibrillar bundle - very insoluble

Question 28

what does the apical region consist of in fungal hyphae

Answer 28

Secretory vesicles
W/. Glucan synthase, chitin synthase, enzyme activators, protease, cell wall lysis enzymes