Introduction Flashcards
What limits life on Earth?
Temperature, pH, water availability, radiation, nutrients
Give four examples of Earth processes that are catalysed by microorganisms
Maintaining chemical balance, mineral formation, mineral diagenesis, mineral dissolution
What groups are prokaryotes?
Bacteria and archaea
Describe prokaryotes
No nucleus or organelles, small, no meiosis, single DNA molecule
Describe eukaryotes
Nucleus, organelles (inc. mitochondris, chloroplasts), meiosis, chromosomes
What does meiosis lead to?
Genetic variation
Compare the suitable conditions for prokaryotes versus eukaryotes
Prokaryotes are much less limited by conditions, including temperature, pH, salinity, and organic/inorganic energy sources
Define heterotrophy
Gaining energy and carbon for growth from the oxidation of organic compounds
Define autotrophy
Forming nutritional organic substnaces from simple inorganic substances
Fixing its own nitrogen
Define chemolithotrophy
Gaining enegry from oxidation of inorganic compounds, taking up carbon as CO2, HCO3^-, or CO3^2-
Give six examples of elements needed by microorganisms
Carbon, nitrogen, phosphorus, sulphur, iron, trace elements
What do microorganisms need for the production of ATP?
Electron donor and electron acceptor
What are electron donors? Give two examples
Elements/moleucles that act as oxidising agents
Glucose and Fe(II)
What are electron acceptors? Give an example
Elements/molecules that act as reducing agents
Oxygen
Describe energy metabolism
Electron flow from fuels to oxidants