Chapter 31 Flashcards
there is an estimated __________ species of fungi
1.5 million
Fungi are _________ and absorb nutrients from outside of their bodies
heterotrophs
Fungi exhibit diverse lifestyles, which includes…
- Decomposers
- Parasites
- Mutualists
Multicellular fungi are made up of _______
hyphae
Most fungi have hyphae divided into cells by ______, with pores allowing cell-to-cell movement of organelles
septa
Coenocytic fungi
lack septa and have a continuous cytoplasmic mass with hundreds or thousands of nuclei
haustoria
specialized hyphae in some unique fungi that allow them to penetrate the tissues of their host
Mycorrhizae
mutually beneficial relationships between fungi and plant roots
Ectomycorrhizal fungi
form sheaths of hyphae over a root and also grow into the extracellular spaces of the root cortex
Arbuscular mycorrhizal fungi
extend hyphae through the cell walls of root cells and into tubes formed by invagination of the root cell membrane
Fungal nuclei are normally _______, with the exception of ____________ stages formed during the sexual life cycles
haploid; transient diploid
pheromones
sexual signaling molecules used by fungi to communicate their mating type
Plasmogamy
the union of cytoplasm from two parent mycelia
heterokaryon
the mycelium in which the haploid nuclei from each parent coexist before they fuse (doesn’t happen right away)
dikaryotic
the name for the mycelium in some fungi with a haploid nuclei pair
karyogamy
nuclear fusion in fungi
T/F: Hours, days, or even centuries may pass before karyogamy occurs
True
________ produce haploid spores by mitosis and form visible mycelia
Molds
T/F: Fungi and plants are more closely related to each other than they are to animals or other eukaryotes
False; fungi and animals are closely related
Fungi are most closely related to unicellular _________
nucleariids
Chytrids
found in terrestrial, freshwater habitats; diverged early in fungal evolution
Chytrids are unique among fungi in having __________ spores, called ________
flagellated; zoospores
Zygomycetes
include fast-growing molds, parasites, and commensal sybionts
zygosporangia
sexually produced by zygomycetes
Zygosporangia is the site of __________ and then ________
karyogamy; meiosis
Ascomycetes
produce secuela spores in the saclike sci contained in fruiting bodies called ascocarps
asci
the saclike body where sexual spores in ascomycetes
ascocarps
the fruiting bodies surrounding the asci
conidia
the asexual spores that come in enormous numbers that allow ascomycetes to reproduce asexually
Basidomycetes
fungi that produce spores in the basidium
basidium
a transient diploid stage in a basidiomycete life cycle
Lichen
a symbiotic association between a photosynthetic microorganism and a fungus (often a ascomycete)
