Environmental Control of Metabolism Flashcards
Name 3 types of micro-organism.
Archaea, bacteria and some eukaryotes
3 reasons micro-organisms are used.
- adaptable
- ease of cultivation
- speed of growth
What is biosynthesis?
Making natural products through enzyme reactions
Give 3 examples of complex molecules required for biosynthesis.
- amino acids
- vitamins
- fatty acids
What is the energy source for photosynthetic micro-organisms?
light
Why are sterile conditions important in a fermenter?
Reduces competition with the required micro-organism.
Other than sterile conditions, name 3 other factors that need to be controlled in a fermenter.
- pH
- Temperature
- Oxygen levels`
What happens during the lag phase?
enzymes are induced to metabolise substrates
What name is given to the phase with the most growth?
log/exponential phase
Why is there so much growth during the log/exponential phase?
plentiful supply of nutrients
State 2 reasons for the stationary phase.
- nutrients in the culture media becoming depleted
2. The production of toxic metabolites
What are secondary metabolites?
Substances produced that are not essential for growth, development and reproduction.
Give an example of a secondary metabolite.
antibiotics
What is the advantage of these secondary metabolites to the organism that produces them?
Allows them to outcompete other micro-organisms.
State 2 things that causes the death phase?
- toxic accumulation of metabolites
2. lack of nutrients in the agar
