Ch. 12 Exam
zygospore
-2 fused hapoild nuclei -forms when nuclei of two similar cells fuse
pseudohyphae
-Filamentous growth by fungi that otherwise are more yeast like than mold like. -The production of buds that fail to detach themselves.
Describe how sexual spores form and how they are similar or dissimilar to the parent fungi.
-Sexual spores form from the fusion of nuclei from two opposite mating strains of the same species of fungus. -Sexual spores require two different mating strains and so are made less frequently than asexual spores. -Organisms that grow from sexual spores will have genetic characteristics of both parental strains, but are also genetically unique.
Know the different types of conidiospores that may be produced. Be able to recognize pictures of them or describe how they appear.
-arthroconidia -blastoconidia -chlamydoconidium
From what source(s) do fungi primarily obtain nutrition? How do they obtain the nutrition?
-decompose organic matter -secrete enzymesto digest matter & absorb broken down matter
Are asexual spores enclosed or not?
-depends on which type -conidiospores (conidium, plural: conidia) which are not enclosed in a sac -sporangiospore which are enclosed in a sac.
Know and understand the life cycle of Rhizopus as an example of fungal asexual reproduction.
1. aerial hyphae produces a sporangium 2. sporangium bursts to release spores 3. spore germinates to produce hyphae 4. vegetative mycelium grows
What temperature drives mold like growth?
25 degrees C
What temperature drives yeast like growth?
37 degrees C
Know and understand the life cycle of Rhizopus as an example of fungal sexual reproduction.
4. vegative mycelium grows 5. gametes form at tip of hypha 6. plasmogamy 7. zygospore forms 8. karyogamy and meiosis 9. zygote produces a sporangium 10. spores are released from sporangium 11. spore germinates to produce hyphae 12. vegetative mycelium grows
Describe what asexual spores form from and how they are similar or dissimilar to the parent fungus
Asexual spores are formed from the hyphae of one organism through mitosis. When these spores germinate, they become organisms that are genetically identical to the parent.
What are the two main types of asexual spores formed by fungi?
Conidiospores and Sporangiospores
coenocytic hyphae
Do not contain septa
True OR False All fungi can reproduce sexually and asexually.
False
hyphae
Filaments of fungi
Through what two ways can a fungus asexually reproduce?
Fragmentation & regrowth of their hyphae & via the formation of spores that detach from the parent and germinate through mitosis and subsequent cell division, no fusion of the nucelus
thallus
Fungal body
Which of these groups consists only of obligate intracellular parasites?
Microsporidia
what way can fungi sexually reproduce?
Sexual spores are formed through sexual reproduction via three phases: plasmogamy, karyogamy &meiosi
karyogamy:
The (+) and (-) nuclei fuse to form a diploid zygote nucleus
True OR False Fungi reproduce asexually and sexually via the formation of spores that detach from the parent and gerninate into the new mold.
True
True or False: After sexual spores are produced, they too may undergo mitosis to be distributed in greater numbers
True
plasmogamy:
a haploid nucleus of a donor cell (+) penetrates the cytoplasm of a recipient cell (-), fusion or marriage of cytoplasm
Describe the common oxygen requirements for fungi:
aerobic or facultative anaerobic
blastoconidia
buds from parent cell
What term would you use to describe the way fungi obtain both carbon and energy?
chemoheterotrophic
Basidiomycota:
club fungi, septate hyphae, produce asexually: conidiospores, produce sexually: basidiospores (formed externally on a base pedestal called a basidium)
Zygomycota:
conjugation fungi, have coenocytic hyphae, they produce asexually: sporangispore by sporangispores and sexually: zygospore (2 fused haploid nuclei).
septate hyphae
contain cross walls have partitions called septa
septa
crosswalls that divide hyphae into compartments
meiosis:
diploid nucleus produces haploid nuclei (sexual spores, genetically unique from parental fungi, but with genes of each)
fission yeasts
divide evenly
budding yeasts
divide unevenly
sporangiospore
enclosed in a sac
arthroconidia
fragmentation of septate hyphae
myco
fungus
aerial hyphae
involved in reproduction
mycellium
mass of hyphae
What makes mold different from yeast?
molds are filamentous, yeasts aren't molds are fuzzy, yeasts aren't yeasts are unicellular
Microsporidia:
no sexual reproduction observed, but probably occurs in a host, no mitochondria, obligate intracellular parasites, we have little info on these, not a virus but is similar in what they do
conidiospore
not enclosed in a sac exposed
vegetative hyphae
obtain nutrients
Understand the three key phases of fungal sexual reproduction as described in your book.
plasmogamy karyogamy meiosis
Ascomycota:
sac fungi, septate hyphae, most telemorphic (produce sexually & asexually), some are amorphic (lost ability to produce sexually), produce asexually: usually conidiospores by conidiophores, produce sexually: ascspores (nuclei morphologically similar or dissimilar fuse in a saclike ascus)
chlamydoconidium:
spore within a hyphal segment
mycology
study of fungi
dimorphism
the ability of some organisms, such as fungi, to exist in 2 forms: yeast like and mold like