KA6 Flashcards
(13 cards)
three things microoganisms can be?
archaea, bacteria, some eukaryote
why are microorganisms used?
because of their adaptability, ease of cultivation and speed of growth
what can microorganisms do?
produce all complex molecules required for biosynthesis
to grow cells in culture, they must be supplied with growth media and correct environmental conditions..
sterility, temp, pH, gaseous environment and light
why are semi-logarithmic graphs used to show cell growth?
the cell number from exponential phase so large after few hours it becomes difficult to plot all points accurately on normal graph scale
what a viable cell growth?
cell counts involving only living microorganisms
what are total cell counts?
cell counts that involve counting viable (living) and dead cells
lag phase
period when microorganisms are adapting to new growth environment
exponential phase
in growth the doubling of cells number every cycle
stationary phase
period when growth and death rates balance each other
death phase
period when microorganisms are dying
secondary metabolism
metabolism which occurs in stationary phase of microbial growth
why are sterile conditions required for growing microorganisms in lab?
it eliminates any effects of contaminating microorganisms, these would compete with desired microorganisms for nutrients and increase risk of spoilage product
