Plants: Lecture 7 Flashcards
Examples of fungi?
- Bread yeast
- Pizza crust yeast
- mushrooms
- Athlete’s foot
- Ringworm
- Black bread mold
- Beer and wine yeast
Characteristics of fungi?
- Heterotrophs (don’t make their own food)
- Eukaryotic
- Main body is haploid
- Can be multicellular or unicellular (yeast is unicellular)
- Cell wall made of chitin (Polysaccharide that makes up arthropod shells, squid beaks and fish scales)
- External digestion of food
- ~120,000 species have been described
What are Hyphae?
Extensions that form a network called a mycelium.
2 kinds of hyphae?
Septate: have divisions between different areas. contains a pores that allow certain items through
Coenocytic: No septums controlling flow and no division whatsoever.
Examples of specialized hyphae?
Predators: makes a noose/snare to trap worms and kill them
Haustoria: go through cell walls and have a symbiotic relationship typically
How do fungi grow?
they digest material outside of their body then bring it inside.
Generalized life cycle?
Typically asexual reproduction
- spores produced with protective coat then germinate (out of coat)
Sometimes go off to sexual reproduction
- Plasmogamy ( 2 cytoplasms with 2 haploid nuclei fuse) creating the heterokaryotic stage with 1n + 1n
- Karyogamy (“fertilization” where nuclei fuse to form 1 diploid)
- Undergoes meiosis to make spores
Spores in fungi?
- Haploid (1n)
- Most are less than 20 micrometers and rarely more than 100
- Each contains a nucleus, dehydrated cytoplasm and a protective coat.
- Can remain dormant for long periods to wait out environment for years sometimes
- Produced by mitosis or meiosis
Purpose of spores in fungi?
- Move to new food source
- Avoid or wait out adverse environment
- Create new genetic combinations by combining 2 genomes
Zygotic Meiosis?
- No sexes beacause no big and small.
- instead we use + or - cells
Types of asexual reproduction in fungi?
- Spores in sporangia
- Conidia spores in conidiophores
- Budding
Fungi are closely related to/
Fungi are closely related to animals
What are the 5 phyla of fungi?
- Chytrids
- Zygomycetes
- Glomeronycetes
- Ascomycetes
- Basidiomycetes
Phylum Chytridiomycota (Chytrids)?
- 1000 species
- single cells or colonies wit hyphae
- Flagellated spore (“zoospore”) that is haploid and asexually produced, swims to move.
- Live in moist environments: aquatic or soil
- Decomposers, parasites, commenals (digestive tract of sheep and cattle)
Spore release in a Chytrid?
It has converted the entire contents of its body into flagellated asexual zoospores.
- Releases these copies as spores for further spread
Amphibian decline?
There has been a massive decline in populations of amphibians and one major cause is due to chytrids that infect the skin.
Phylum Zygomycota (Zygomycetes)?
- 1000 species
- Coenocytic (non-septate) hyphae
- Decomposers, parasites, commensals (live symbiotically)
Entomophthora (insect destroyed)?
Spore infects the animal and the fungus grows, controls the mind of the insect, summiting and head glued down. Consumes the body of the insect and death occurs at dusk.
Pilobolus?
When fluid filled item gets hot enough, it explodes and send the spores flying. They then land on food that cows eat and then they get to their food source.
Black bread mold?
Asexual spores are what we see but there is a large group below.
Zygomycota life cycle?
+ and - unite and forms a diploid nuclei that undergoes meiosis. One huge nuclei
Phylum Glomeromycota (Glomeromycetes)?
- 160 species
- Non-septate hyphae
-Only asexual - Mostly associated with plants
- Obligte symbionts called mycorrhizae which get into the roots and expand to absorb water and minerals. Get in cell walls and grow projections
Phylum Basidiomycota (Basidiomycetes)?
- 30,000 species
- Mushrooms
- Decomposers and ectomycorrhizal
- Long-lived eukaryotic mycelium
- Multicellular
- Septate mycelia
- Multicellular sexual reproduction (fruiting body “basidiocarp” called mushrooms puffballs or brackets)
- Multicellular asexual reproduction: conidia formed by hyphae
Bracket (shelf) fungi?
In dying or dead trees, digest material inside the wood
