fungi - studied by mycologists 

• divided into chytrids, zygomycetes, basidiomycetes, asomycetes
• more closely related to animals than plants
• heterotrophs that live on their food (secretes digestive enzymes)
  • hydrolytic enzymes - breaks down food, lets hyphae grow into food
• multicellular fungi consist of hyphae (long/slender filaments)
• dikaryon stage - in sexually reproducing fungi
  • 2 haploid cells coexist in a single cell for a short period of time
• chitin in cell walls
• mitosis takes place within nucleus (envelope doesn’t dissolve), like protists

fungus structure - made up of hyphae 

• hyphae - made up of cell chains divided by septa (cross-walls)
  • technically still considered a single cell
  • cytoplasm flows freely through filament >> easy for growth
  • only grows in length
  • haustoria - penetrates land, stays outside
• mycelium - mass of hyphae
• hyphae rapidly expands >> reproductive structures form quickly
• spindle apparatus forms within nucleus
  • no centrioles used

fungi reproduction - cells can hold more than 1 nucleus 

• monokaryotic - 1 nucleus
• dikaryotic - 2 haploid nuclei (exists independently of each other)
• heterokaryotic - hyphae w/ nuclei from distinct individuals
• homokaryotic - hyphae w/ genetically similar nuclei
• can produce sexual/asexual spores
• hyphae fuse in sexual reproduction
• reproductive structures closed off from rest of fugae by septa w/ blocked pores
• small spore size >> ability to be suspended in air >> rapid spread of disease

fungi metabolism - absorbs food through external digestion 

• unicellular fungi have greatest SA-to-volume ratio among fungi >> max absorption area
• can digest lignin/cellulose from plant cell walls, nematodes
• used to make fermented goods (soy sauce, miso, wine, cheeses)
• yeast - unicellular fungi
  • breaks down glucose to ethanol, carbon dioxide
• able to break down any compound w/ carbon in presence of water
• bioremediation - using organisms to degrade toxins, clean the environment