Week 6

Question 1

Fungal diversity

Answer 1

-diverse group of heterotrophs
-often decomposers
micro fungi: invisible to naked eye, ex yeasts and molds
macro fungi: produce easily visible fruiting bdoies (mushrooms)

Question 2

list of distinctive traits of fungal diversity

Answer 2

-cell wall (contains glucans and chitin)
-sterol containing cell membrane
-Heterotrophs with absorptive nature
-grow as filament like structures (hyphae)
-produce spores

Question 3

describe the cell wall of fungi

Answer 3

*contains glucans and chitin
○ Inner cell wall highly conserved, made up of chitin and B-1-3-glucan
○ Outer cell wall is variable
○ Many yeasts have outer cell wall made of polysaccharide mannan and mannoproteins

Question 4

Describe the cell membrane of fungi

Answer 4

• Sterol-containing cell membrane
  ○ Ergosterol: sterol similar to animal cholesterol

Question 5

How do heterotrophs break down food

Answer 5

are decomposers of dead organic matter (called saprotrophs), must break down food extracellularly

Question 6

how do fungi form hyphae

Answer 6

• Grow as extended filament like structures (hyphae)
  ○ Different forms
  ○ Mycelium: branched and extending mass of hyphae that can differentiate into spore-forming structures
  ○ Have spore that germinates, extends to form hyphae, branches and forms mycelia (entire collection of hyphae

Question 7

how do micro and macro fungi produce spores

Answer 7

○ Grows within food source
○ Dormant structure formed to resist environmental stress
○ Has sexual and asexual life cycles (mitosis)
§ Produce sexual spores in sexual fruiting bodies
§ Produce asexual spores in asexual fruiting bodies

Question 8

What is symbiosis

Answer 8

• During evolution organisms adapt to presence of other
  
  • Can be positive or negative relationships both evolve in response to each other

Commensal, Parasitic, or Mutualism

Question 9

What is Commensal symbiosis

Answer 9

one benefits, other is unaffected

Question 10

What is parasitic

Answer 10

one benefits, harms other host

Question 11

What is mutualism

Answer 11

each gains benefits, may fail to grow independently, can involve 2+ partners, removal of partner leads to decreased growth or death of host
§ Ex: Lichens and algae: cannot survive independently
§ Photosynthetic algae or cyanobacteria acts as photobiont that receives nutrients from the fungi
§ Fungi receives carbs produced by the algae/cyanobacteria
§ Fungi physicalyl protects the photobiont