Fungi

Question 1

Phylogeny

Answer 1

• One of three major lineages of terrestrial eukaryotes
• colonized land much before plants
• went from single cells (yeast) to huge multicellular structures
• critical for a functional ecosystem

Question 2

Structure of Fungi

Answer 2

• single celled or made of filaments
• no complex transport system
• cell walls but common chitin
• yeast = single cells
• mycelia (made of hyphae, long, thin filaments)
• Hyphae (separated by cross-walls called ‘septa’
• septa (large pores allow passage of nutrients)
  all packs together to form mushrooms

Question 3

Nutrition of Fungi

Answer 3

• Thin hyphae = master absorbers
• need moisture -> often symbiotic
• secretes digestive enzymes externally (saprophytes, symbionts)
• there is diversification driven by nutrient absorption
• key in C,N,P cycles
• main decomposers of cellulose and ligin

Question 4

What is the difference between yeast and bacteria?

Answer 4

Bacteria are prokaryotes (no membrane around nucleus)

Yeast is eukaryotes (nucleus bound in membrane)

Question 5

Reproduction of Fungi (asexual and sexual)

Answer 5

Asexual: fragmentation, during haploid phase, vegetative spores, produced on conidiophores
Sexual: gill mushrooms, one species can have many mating types, if individuals are compatible they fuse mycelia to initiate (nuclei fuse, meiosis, spores)

Question 6

Define Basidia

Answer 6

Specialized end cells of mushroom gills

Question 7

Dispersal (fungi)

Answer 7

• spores tolerate dry conditions
• spores are important for dispersal, they are small so they can be airborne
• some have ejection mechanisms, some use animal dispersers

Question 8

Humans & Fungi

Answer 8

• edible mushrooms
• breakdown of sugars –> alcohol & C02
• fermentation
• mycotoxins
• bio control ect.