Fungi

• Mycology


  The study of fungi
• Fungus


  • Eukaryote
  • Lacks rigid cell wall
  • Motile (some)
  • Photosynthetic (some)
  • Chemotrophic (degrade organic substances)
• Fungi grow at 20-22°C
• Molds


  • Large multicellular aggregates of long branching filaments (hyphae)
  • Hyphae responsible for appearance of mold colony
  • Fluffy, wooly, cottony, velvety, verrucose appearance
  • Spores produced at ends of aerial hyphae
  • Resistant to heat, drying, and freezing
  • Contain glycogen or lipid energy reserves
  • Thicken cell walls under unfavourable conditions
  • Easily aerosolized
• Septate hyphae


  Filaments with cross walls (septa)
• Aseptate hyphae


  No cross walls
• Fungi absorb nutrients from the environment and transport them to other parts of the thallus (fungus body)
• Yeasts


  • Large single unicellular
  • 30-35°C (body temp) 5-8 μm diameter
  • Produce bacteria-like colonies on solid media
  • Spherical or ellipsoidal
  • Reproduce mainly by budding (blastospores)
• Fungi can switch between yeast and mold forms to adapt to different temperatures and spread in human tissue
• Fungal cell structure


  • Capsule composed of polysaccharides
  • Selective cell membrane with ergosterol rather than cholesterol
  • Target for antifungal drugs
• Molds found in damp, dark, vaporous environments
• Yeasts found in fruit, berries, skin, stomach
• Fungi can cause mycosis (fungal infections) in animals and humans, ranging from superficial skin/hair infections to deep systemic infections
• Pores


  • Large round thick, walled
  • Unicellular structure
  • Resistant to heat, drying
• Parangios plates


  • At the end of sporangis
  • Hypne sac like struct
• Glycogen


  Lipid reserves
• Energy


  Produced in lack of nutrients or unwanted conditions
• Arthroconiline


  • Hyphat cells thicken their cell walls
  • Easily aerosolized, forming barret shape conidia
  • Unicellular, small spores
• Macroconidia


  • Multicellular
  • Useful in identification
• Yeasts


  • Large single unicellular
  • 30-37C (body temp)
  • 5-8 μm diameter
• The life cycle of fungi includes both asexual (vegetative) and sexual stages.
• Sexual reproduction is important for fungi to produce genetically diverse offspring that can adapt to changing environments.