SME
Microbiology · Problem type
The phases of the growth curve
Use this for “Put the lag, log, stationary and death phases of a batch culture in order, and say why each happens.”
Put in order
Put the phases of a batch culture in order, from inoculation.
1
?
2
?
3
?
4
?
Assumptions
•
The culture grows in a closed flask of broth: no food is added and no waste is removed (a batch culture).
•
The curve plots the log of the living cells against time, so steady doubling draws a straight rising line.
•
Each phase’s length is typical for a fast-growing bacterium; it changes with the species, the medium and the temperature.
Topic check
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