unit 6 part 3

Unit 6 Part 3

Fungi

Characteristics

• Eukaryotic heterotrophs

• Multicellular (except yeasts)

• Cell wall– Made of chitin

Characteristics

• Digest food outside of their bodies and then absorb it

– Some absorb decaying matter in the soil (saprotrophic decomposers)

– Some are symbiotic (lichen, plants)

– Some are parasitic – absorb nutrients from host

Characteristics• Fungi as parasites:

– Plant diseases (mildew, corn smut)

– Human diseases (foot fungus, yeast infections)

– Other animal diseases (Cordyceps fungus)

Fungal Disease

Fungal Disease

Fungal Disease

Structure & Function

• Composed of thin filaments called Hyphae

• Hyphae are tangled together in a thick mass called mycelium

• Large surface area for absorbing nutrients

Structure & Function

• Fruiting body – reproductive structure; grows from the mycelium in the soil

• Can have many f.b.’s emerging from same mycelium

Structure & Function

• Mycelium can live for many years

• Over time…nutrients are depleted from soil around them…Why?

• Result…

Structure & Function

• Fairy Rings

• New fungi sprout at edges of mycelium, forming rings.

Reproduction

• Asexual:

– Cells/hyphae break off + grown on own

– Scattered spores (reproductive cell; grows into new org. through mitosis alone)

Reproduction• Sexual:– No “male/female”– Called “+” and “-”– Hyphae from + and – fuse together and produce a diploid

zygote

Classification

• Common Mold– Black bread mold

• Sac Fungi– Largest group of

fungi– Includes yeasts

Classification

• Club Fungi– Reproductive

structures look like clubs

– Extremely diverse