The Population Growth Curve

The population of bacteria does not maintain its potential growth rate and does not double endlessly because it is in a ______ _______ . Numerous factors limit the exponential growth rate.

Closed systems

Because there are ____ cells in the early stages of growth, very early samples can give a ____ reading even if there are viable cells in the culture

Few

Zero

The system of batch culturing is ____, meaning that nutrients and space are FINITE and there is no mechanism for the removal of waste products.

closed

The ______ phase is relatively “flat”

lag

When the population appears not to be growing or is growing at less than exponential rate

Lag phase

Growth ___ primarily because the newly inoculated cells require a period of adjustment, enlargement, and synthesis.

Cells are not yet multiplying at their maximum rate

lags

The cells reach the maximum rate of cell division during the _________ ______ or __________ phase.

exponential growth

log

The log phase will continue as long as the cells have _______ nutrients and the environment is ______

nutrients

favorable

The the _______ _______ phase, the population enters a period during which the rates of cell death and cell birth are more or less equal

stationary growth

The decline in the growth rate is caused by depleted ______ and ______ plus excretion of organic acids and other biochemical pollutions into the growth medium, due to the increased density of cells

nutrients

oxygen

As the _____ _____ intensify, cells begin to die at an exponential rate.

Limiting factors

The curve now dips downward as the ____ _____ begins

death phase