The Study of Fungi is called Mycology Kingdom Fungi The Study of Fungi is called Mycology What is probably the largest living organism on earth has been discovered in the Malheur National Forest in eastern Oregon. A fungus living three feet underground is estimated to cover 2,200 acres. After testing samples from various locations, scientists say it is all one organism. Officially known as Armillaria ostoyae, or the honey mushroom, the fungus is 3.5 miles across and takes up 1,665 football fields. The small mushrooms visible above ground are only the tip of the iceberg. Experts estimate that the giant mushroom is at least 2,400 years old, but could be 7,200 years old.
Members of the Kingdom Fungi are: Multicellular, except for Yeasts which are single-cellular Are all Eukaryotes Are All Heterotrophs.. “Absorptive Feeders” Most have cell walls made of Chitin (sugar) Most are sedentary ..(they don’t move around, they live their lives anchored somewhere)
Foods are digested using enzymes. Fungi are “Exofeeders” … they digest their foods externally before they ingest (absorb) the digested nutrients through their cell walls. Foods are digested using enzymes.
Fungi live and grow in their food….. Fungi can Facts Fungi live and grow in their food….. Fungi can only be seen when their fruiting bodies emerge…. By then it’s too late!
Facts Cell Walls are either partial or absent………. The cytosol is circulated through simple cyclosis.
Ecological Role Fungi are the great recyclers …. The major role of Fungi is as Decomposers Fungi are the great recyclers …. They are Saprophytes…they feed on organic compounds that they absorb from dead organisms in the environment.
Fairy Rings
The Life Cycle of a Fungi Spores Hypha Mycelium Fruiting Body (haploid reproductive cell) (a single filament) (a mass of hyphae) (reproductive and dispersion of spores)
Fungi begins as a Spore. Spores are single, haploid (n) reproductive cells.
A Spore germinates and develops a Hypha. Nutrient Hypha/Filament
The cell walls of Fungi are made of Chitin. (Chitin is made up of sugars… the same substance which makes up the exoskeleton of insects.) Cell Wall
Some fungi have cross walls, or septa, which divide the hyphae into individual cells each having a single nucleus. Septum (sng.)
Some cells lack septa and are multi-nucleated, or coenocytic (have many nuclei).
The Hyphae branches as it digests its way through the food.
A Mass of Hyphae forms the Mycelium Mycelium located at the base of Mushroom stalks. Mycelium in soil and leaf litter.
The Mycelium growth in a Petri Dish
What looks like dust is actually spores being released. When conditions dictate the Mycelium develops into a Fruiting Body which produces Spores. What looks like dust is actually spores being released.
Fossil records show they first appeared about 460 MYA. Evolution Fungi arose through Endosymbiosis from early prokaryotes. Fossil records show they first appeared about 460 MYA.
*** Sexual Reproduction occurs through Conjugation. Fungi Reproduction Fungi reproduce both sexually and asexually 3 Types of Asexual reproduction 1. fragmentation: the breaking up of hypha 2. budding: the pinching off of a small hypha outgrowth 3. asexual spores: dispersing haploid (n) reproductive cells *** Sexual Reproduction occurs through Conjugation. Conjugation is the process by which two organisms exchange or join their DNA.
Classification of Fungi mostly classified by the shape of the “Fruiting Bodies” The “Fruiting Bodies” are the reproductive structures. Phylum Zygomycota (molds, bread mold, etc..) Phylum Basidiomycota (mushrooms, puff balls, bracket fungi) Phylum Ascomycota (cup fungi, yeast) Phylum Deuteromycota (Imperfect fungi)
Phylum Zygomycota (The Molds) Bread Mold 1000 x
A nice bowl of mold…The Zygomycetes
Want an orange ? The Zygomycetes do!!
Asexual Reproduction of Bread Mold Zygosporangia: Produces the sporangiospores Sporangiophore: Holds up the sporangium
Asexual Reproduction
Fungal Conjugation (Sexual Reproduction)
Phylum Basidiomycota “Club Fungi” Mushrooms Puffballs Shelf (Bracket) Fungi Underground mycelia grow upward to produce a reproductive structure called a basidiocarp. This basidiocarp is what we call a mushroom. Basidiospores are produced on the basidia, reproductive structures, which are found on the edges of the gills.
Structures of a Mushroom Fruiting Body Cap Gills made up of Basidia ….Which produce the Basidiospores. Stalk: Holds the Cap above the ground…. Aids in spore dispersion. Mycelium (hyphae) and soil
The Basidia “clubs” produce the spores (basdiospores) Basidiospores Gills: made up of basisdia Basidium
Various Types of Basidiomycetes
Agaricus (gills) Amanita phalloides “Death Cap”
Boletes: tubes instead of gills
Chanterelles: vase-shaped
Morels
Puff Balls
Shelf, or Bracket Fungi Common Name: Turkey Tails
Phylum Ascomycota “Cup Fungi” Yeast Mildews The largest group of fungi Named for the reproductive cups or Asci. Ascospores are formed here and released into the air when the asci rupture. These spores germinate to form new hyphae.
Yeasts (Saccharomyces) 400X Unicellular Fungi used to Genetically engineer Vaccines Yeasts reproduce by “Budding”. Budding is an Asexual form of reproduction. Buds Yeast Cell Bud Yeast Cell
Yeast cell Budding 1000X (asexual reproduction) Yeast Cell and bud Budding Continues 2 Resulting Yeast Cells
Cup Fungi - Ascocarps
Asexual Spores When magnified the insides of the cups are made of thousands of tubes, each tube is called an ascus… the ascospores form inside the asci (tubes). ascus ascospores Asci: inner lining of the cup.
Cup Fungi: Bird’s Nest Spore Packets
Phylum Deuteromycota “Imperfect Fungi” Athlete’s Foot Ringworm Penicillium Called “imperfect” because a sexual reproductive stage has not been observed.
Penicillium: source of penicillin notice the shape of the fungus… a disc
Athlete’s Foot
Athlete’s Foot
Ringworm
Ringworm
Many Fungi are involved in Mycorhizzae relationships…Over 90% of plants have fungi living near or on with their root systems. The Fungi absorb and concentrate minerals, and nitrogen, for the plant roots. In return, the fungus receives sugars synthesized by the plant. lack septa don’t produce zygospores
Common Industrial Uses for Fungi Used to make Antibiotics…Penicillium mold used to produce Penicillin Yeast used in Baking Yeasts used in Genetic Engineering Used a Foods Used to Detoxify water and soils Used to make Gasohol.
The Wrong Fungi can Kill You!! WHY? They can infect internal organs… such as your liver, kidneys, lungs, etc…. They can contain potent toxins! They can induce lethal allergic reactions! Very Few are Edible…and they are very hard to identify!! Their SPORES alone can kill you!
A mutualism consists between the fungi and the photosynthetic algae. Lichen A mutualism consists between the fungi and the photosynthetic algae. The algae provides food, the fungus provides the physical environment by trapping water and giving the algae a place to live. The chemical decomposition of rocks by lichens contributes to the production of soils.
Lichen has 3 stages of growth 1. Crustose 2. Foliose 3. Fruticose
Crustose…looks like crust
Foliose… leafy appearance
Fruticose…. Shrub-like
The Fungal Fruiting Bodies in Lichen
The End