microbiology

• What percentage of Earth's life history was exclusively microbial?

  80%
• How long have microorganisms lived on Earth compared to humans?

  About 3.5 billion years longer
• What are the first oxygen-producing microorganisms?

  Cyanobacteria
• What are the three lineages of all life on Earth?

  Bacteria, Archaea, Eukarya

  
• What does LUCA stand for?

  Last universal common ancestor
• What role do fungi play in the ecosystem?

  • Primary decomposers
  • Sequesters of carbon
• What do white rot fungi use to degrade cellulose?

  Hydrolases and peroxidases
• What do brown rot fungi break down?

  Hemicellulose and cellulose
• What is the process used by brown rot fungi to break down cellulose?

  Two-step process: active O2 species + enzymes
• What do soft rot fungi break down?

  Hemicellulose and cellulose
• What is the market value of fungi-related products?

  • £32.5 billion per year
  • Used in plastic car parts, synthetic rubber, and LegoTM
• What is itaconic acid derived from?

  Derived from a fungus
• Who first observed microbial cells in 1683?

  van Leeuwenhoek
• first observed 'cells' in 1665?

  Hooke
• What were the two theories regarding the origin of life?

  • Spontaneous generation
  • Biogenesis
• What did Francesco Redi demonstrate in 1668?

  Maggots did not arise spontaneously from meat spontaneously
• What was the key difference in Needham and Spallanzani's experiments?

  • Needham: boiling + incubation (life arose)
  • Spallanzani: sealed, heated media +incubation (life didn't arise)
• What was Pasteur's hypothesis regarding microorganisms?

  Microorganisms were descendants of those already in the material or carried in dust
• What experiment did Pasteur conduct to support biogenesis?

  Swan-neck flask experiment (flask is open to air but bend means no microorganisms can fall from air)- provided definitive proof for biogenesis

  
• What are Koch's postulates?

  • Rules to establish link between microorganisms and disease

  
• Who established the system of scientific nomenclature?

  Carolus Linnaeus
• What are the two rules for naming organisms?

  1. Two names: genus and species
  2. Names are italicized or underlined
• How are organism names shortened after first mention?

  By using initials for genus
• importance of microorganisms

  -decompose organic matter + recycle nutrients

  -bioremediation - break down of pollutants

  -immune development and human health

  -biotechnology

  -food/ drink

  -disease
• what are Koch's postulates

  -pathogens must be present in all cases of disease and absent from healthy animals

  -suspected pathogen must be grown in pure culture

  -cells from pure culture must cause disease in health animal

  -suspected pathogen must be reisolated and shown as the same as the original
• fungi functions

  -consumed as food

  -fermentation

  -citric acid

  -itaconic acid- produces plastics, rubber and latex
• conditions that wouldn't hold Koch's postule's

  -viruses

  -prions

  -intercellular pathogens

  -long carrier state before causing disease

  -toxin mediated disease
• importance of biogenesis

  -food preservation

  -interventions to stop microbial growth

  -sterilisation -infection control

  -understanding cause of infection
• Who proposed the three domains of life?

  Ernst - protista, plantae and animalia
• What is a key difference between prokaryotes and eukaryotes regarding organelles?

  Prokaryotes have no organelles
• How do prokaryotes compare in size to eukaryotes?

  Prokaryotes are smaller
• What type of DNA do prokaryotes have?

  Prokaryotes have circular DNA
• What is the composition of the cell wall in prokaryotes?

  Cell wall is made of peptidoglycan
• What structures are found in prokaryotes that aid in attachment and survival?

  Capsules, fimbriae, and endospores
• What is the size of ribosomes in prokaryotes?

  Prokaryotes have smaller ribosomes
• What are the ribosomal RNA components in prokaryotes?

  16s, 23s, and 5s
• What is a key feature of eukaryotes regarding organelles?

  Eukaryotes have organelles
• How is DNA structured in eukaryotes?

  Eukaryotes have linear DNA in chromosomes
• What is the composition of the cell wall in plant eukaryotes?

  Cell wall is made of cellulose
• What is the composition of the cell wall in fungi?

  Cell wall is made of chitin