Evolution of Unikonta: Fungi

Question 1

Unikonta

Answer 1

• Includes certain amoebae and opisthokonts (fungi, choanoflagellates and animals)
• Heterotrophic
• Mostly single flagellum (if they have one)
• Fungi were likely the first found on land

Question 2

Fungus among us:

Absorptive Heterotrophs

Answer 2

• Absorptive heterotrophs: release enzymes to digest complex molecules, then absorb smaller molecules

Question 3

Fungus among us:

What are the walls composed of?

Answer 3

• Walls composed of chitin

Question 4

Fungus among us:

Phases

Answer 4

• Trophic Phase
  -> Hyphae network
  (mycelium)
  around/in
  food sources
• Reproductive phase
  -> Fruiting body
  -> Produces spores

Question 5

Fungus among us:

Ecological Roles

Answer 5

• Decompose Organic Matter
• Symbiotic relationships
• > Mycorrhizae associations with most plant species (enhance nutrient uptake)
• Edible
• Production of cheeses, bread, wine and beer
• Medical uses (antibiotics)

Question 6

Fungus among us:

Economic Roles

Answer 6

• Edible
• Production of cheeses, bread, wine and beer
• Medical uses (antibiotics)

Question 7

Fungus among us: 
Negative effects (to humans)

Answer 7

• Spoil/decompose cloth, food crops, wood, parasitize plants and animals
• Pathogens cause health problems
• > Athletes foot
• > Ring Worm
• Some produce toxins (poison our food)
• Some toxic to eat

Question 8

Fungus among us:

Cycles

Answer 8

Slide 9:

https://lms.unb.ca/d2l/le/content/161564/viewContent/1704185/View?ou=161564

Question 9

Different types of Fungi

Answer 9

• Chytrids
• Zygomycetes
• Glomeromycetes
• Ascoomycetes
• Basidiomycetes

Question 10

Chytrids

Answer 10

• 1000 species
• Ubiquitous (found, present) in lakes and soil
• Decomposers but also parasitic (of protists, other fungi, plants, animals)
• Batrachochytrium dendrobatidis is likely responsible for the global decline of amphibians (animals that need moist environments in order to live)

Question 11

Zygomycetes

Answer 11

• 1000 species
• Many fast growing and responsible for food moulds
• Some parasitic or commensal symbionts

Question 12

Glomerocytes

Answer 12

• 160 species but very ecologically significant
• Almost all form arbuscular mycorrhizae
• 80% of plants have mutualistic relationships with glomeromycetes

Question 13

Ascomycetes

Answer 13

• 65000 species
• Include yeasts, cup fungi, truffels and morels
• > any plant pathogens
• > Decomposers
• > Food and pharmaceuticals
• Trophic Phase: haploid hyphae (exceptions in yeast)
• Fruiting body = ascocarps
• Spores produces in asci (saclike structure), and discharged

Question 14

Basidiomycetes

Answer 14

• 30000 species
• Include mushrooms, shelf fungi, rusts and puffballs
• Decomposers of wood (lignin)
• Trophic phase: haploid and dikaryotic
• Fruiting body = basidocarp (dikaryotic)

Question 15

Size of Fungi

Answer 15

Blue Whale 
- 2 or 3 in end zone of football field 
Armillaria ostoyae
- 965 hectares (1800 football fields)
- Hundreds of tons 
- >1900 years old
Stand of Aspen 
- 45 hectares (85 football fields) 
- 6000 tons 
- >80000 years old

Question 16

Lichens

Answer 16

• Symbiosis: cyanobacteria and/or green algae and fungi
• > Algae fix C (and N by cyanobacteria)
• > Fungi provide structure and habitat for algae (retain H2O, secrete acids to dissolve minerals, provide protection)
• Live in most environments: 1st to colonize new/harsh habitats