FUNGI

22-1 Characteristics of Fungi

22-2 Fungal Diversity

22-3 Fungal Associations

Fungi Kingdom

Fungi are heterotrophic – the stalk and the cap of a mushroom are not green like the leaves of a plant; plants appear green because they contain chlorophyll; fungi do not contain chlorophyll; fungi obtain energy by absorbing organic molecules from their surroundings

Fungi Kingdom• Fungi have filamentous bodies – the long slender filaments

weave tightly together to form the fungus body and reproductive structures

• A giant fungus of the species Armillaria ostoyae in the Malheur National Forest in Oregon was found to span 8.9 km² (2,200 acres), which would make it the largest organism by area.

Fungi Kingdom

• Fungal cells contain chitin – cells of all fungi have walls made of chitin (the tough material found in the exoskeleton of insects and other arthropods)

Fungi Kingdom• Fungi have nuclear mitosis – in plants/animals

the nuclear envelope disintegrates during mitosis; in mushrooms the nuclear membrane remains intact and mitosis is complete when the nuclear membrane pinches in two

Fungi Structure• Hyphae – slender

filaments that make up fungi bodies

• Mycelium – tangled mass of hyphae

Fungi are Heterotrophic

• Fungi digest food outside their bodies

• Hyphae tips secrete powerful digestive enzymes that break down organic matter

Fungi are Decomposers• In their search of food, many fungi attack

nonliving organic matter and decompose these materials.

• Other fungi absorb nutrients from living hosts, which sometimes become weakened and succumb to infection or disease.

Fungi Reproduction

• Fungi reproduce by releasing spores.• Spores form in reproductive

structures (basidia) at the tips of hyphae.

• Reproductive structures (mushrooms) extend high above the food source so that air currents can carry the spores to a new habitat.

• When a spore lands in a suitable place, it begins to divide and soon gives rise to a new fungal hypha.

SPORES

• Spores are usually haploid and unicellular and are produced by meiosis in the sporophyte.

• a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions.

• A chief difference between spores and seeds as dispersal units is that spores have very little stored food resources compared with seeds.

• Once conditions are favorable, the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte.

Phyla of Fungi

• Zygomycota: black bread molds• Ascomycota: morels, truffles, yeasts, cup

fungi• Basidiomycota: mushrooms, puffballs,

rusts, smuts• Deuteromycota (Fungi Imperfecti - sexual

reproduction has not been observed): Penicillium, athletes foot, ringworm, blue cheese mold

Fungal Associations• Lichen – symbiotic association

between a fungus and a photosynthetic partner in which the fungal partner protects the photosynthetic

•Mycorrhizae – symbiotic association in which a fungus transfers minerals to a plant’s roots, which in turn supply carbohydrates to the fungus

Fungi Quiz

Label the parts of the mushroom

Fungi Quiz

• What substance makes up the cell walls of fungi?

CHITIN

Fungi Quiz

• How do fungi obtain energy?

FUNGI ARE HETEROTROPHIC DECOMPOSERS.

THE HYPHAE TIPS SECRETE AN ENZYME THAT BREAK DOWN ORGANIC MATERIAL.

Fungi Quiz

• How do fungi reproduce?

FUNGI REPRODUCE BY SPORES.

Fungi Quiz

• Molds belong in the ________ phylum.

ZYGOMYCOTA

Fungi Quiz

• Yeast belongs in the __________ phylum.

ASCOMYCOTA

Fungi Quiz

• Mushrooms belong in the __________ phylum.

BASIDIOMYCOTA

Fungi Quiz

• Describe the symbiotic association that occurs in lichen.

A fungus and a photosynthetic partner in which the fungal partner protects the photosynthetic partner

Fungi Quiz

• Describe the symbiotic association that occurs in mycorrhizae.

Fungus transfers minerals to a plant’s roots, which in turn supply carbohydrates to the fungus

Vocabulary – Due Monday

• Ascocarp• Ascus• Basidium• Chitin• Dikaryon• Dikaryotic• Ectomycorrhizae• Endomycorrihizae

• Endomycorrihizae• Hypha• Fungi imperfecti• Lichen• Mycelium• Septa• Yeast• Zygosporangia

Fungus Survey

• Day 1 – Mushroom and Yeast

• Day 2 – Mold and Lichen

Mushroom

• Diagram mushroom – label cap, stem, gills