environmental control of metabolism 2.6 Flashcards
what are the three microorganism types
archeria
bacteria
eucariotes
why are microorganisms useful
adaptable
speed of growth
produce helpful products from their metabolic pathways
what is the growth of a microorganism influenced by
environmental conditions
growth medium
name the molecules microorganisms produce required for biosynthesis
amino acids
fatty acids
vitamins
what is needed for culturing microorganisms in their growth media
biosynthesis materials
energy source
what is an energy source derived from
chemical substrates or
light
what are the culture conditions
sterility
temp
oxygen
ph
why is sterile conditions in fermentors needed
it reduces competition for nutrients from other microorganisms and reduce the risk of spoilage of products
when microorganisms are cultured in a lquid medium what do they use up and release
use up substrate and nutrients
release metabolites into the medium
what are the four phases of growth
lag
log
stationary
death
what happens in the lag phase
enzymes induced to metabolise avaliable substrates
what happens in log phase
shows the most rapid growth of microorganisms due to plentiful nutrients
what happens in the stationary phase
nutrients in media become depleted and production of toxic metabolites
what is an example of secondary metabolites
antibiotics
what is the death phase
occurs due to toxic accumulation of metabolites and lack of nutrients in culture
