logarithmic growth phase

(noun)

exponential phase (sometimes called the log phase or the logarithmic phase) is a period characterized by cell doubling.

Related Terms

Examples of logarithmic growth phase in the following topics:

  • Preserving Bacterial Cultures

    • While it is possible to make a long term stock from cells in the stationary phase, ideally your culture should be in logarithmic growth phase.

  • Generation Time

    • In autecological studies, bacterial growth in batch culture can be modeled with four different phases: lag phase, exponential or log phase, stationary phase, and death phase .
    • The exponential phase (sometimes called the log phase or the logarithmic phase) is a period characterized by cell doubling.
    • For this type of exponential growth, plotting the natural logarithm of cell number against time produces a straight line.
    • This chart shows the logarithmic growth of bacteria.
    • The phases of growth are labelled on top.

  • Units of Measurement for Microbes

    • Microbial growth is an important measure in understanding microbes.
    • Since there are limits on space, food, and other factors, actual growth never matches actual measured growth.
    • This chart shows the logarithmic growth of bacteria.
    • Note the Y-axis scale is logarithmic meaning that the number represents doubling.
    • The phases of growth are labelled on top.

  • Enrichment and Isolation

    • During lag phase, bacteria adapt themselves to growth conditions.
    • Exponential phase (sometimes called the log or logarithmic phase) is a period characterized by cell doubling.
    • In comparison to batch culture, bacteria are maintained in exponential growth phase, and the growth rate of the bacteria is known.
    • Bacterial growth in batch culture can be modeled with four different phases: lag phase (A), exponential or log phase (B), stationary phase (C), and death phase (D).
    • List the growth phases of microrganisms and the different types of growth media available to culture them

  • Solving General Problems with Logarithms and Exponents

    • Logarithms are useful for solving equations that require an exponential term, like population growth.
    • Logarithms have several applications in general math problems.
    • We can rewrite logarithm equations in a similar way.
    • If you are asked to rewrite that logarithm equation as an exponent equation, think about it this way.
    • This population growth graph shows that it grows exponentially with time.

  • Natural Logarithms

    • The natural logarithm is the logarithm to the base e, where e is an irrational and transcendental constant approximately equal to 2.718281828.
    • The natural logarithm is the logarithm with base equal to e.
    • For example, the doubling time for a population which is growing exponentially is usually given as ${\ln 2 \over k}$ where $k$ is the growth rate, and the half-life of a radioactive substance is usually given as ${\ln 2 \over \lambda}$ where $\lambda$ is the decay constant.
    • Using the power rule of logarithms it can then be written as:
    • The graph of the natural logarithm lies between the base 2 and the base 3 logarithms.

  • Biofilms

    • When a cell switches to the biofilm mode of growth, it undergoes a phenotypic shift in behavior in which large suites of genes are differentially regulated.
    • Recent evidence has shown that one fatty acid messenger, cis-2-decenoic acid, is capable of inducing dispersion and inhibiting growth of biofilm colonies.
    • For instance, the biofilm form of Pseudomonas aeruginosa has no greater resistance to antimicrobials than do stationary-phase planktonic cells, although when the biofilm is compared to logarithmic-phase planktonic cells, the biofilm does show greater resistance to antimicrobials.
    • This resistance to antibiotics in both stationary phase cells and biofilms may be due to the presence of persister cells.

  • Interphase

    • During interphase, the cell undergoes normal growth processes while also preparing for cell division.
    • The centrosome is duplicated during the S phase.
    • There may be additional cell growth during G2.
    • The cell cycle consists of interphase and the mitotic phase.
    • Interphase is followed by the mitotic phase.

  • Growth models

    • Kazanjian and Drazin (1980), for example, developed a four-phase growth model, and identified the typical growth problems of fast-growing firms in each phase.
    • Phase 3, Growth: The fast-growth phase is characterized by its focus on the market.
    • Phase 4, Stability: In this phase the focus lies on consolidating the market position with the initial product, and developing further products.
    • Firm growth does not always develop through the phases of such models in a straightforward, linear way, for example.
    • A period of experimentation is followed by a stabilization phase.

  • Growth Rate and Temperature

    • Bacterial growth is the division of one bacterium into two daughter cells in a process called binary fission.
    • When Escherichia coli is exposed to a temperature drop from 37 to 10 degrees Celsius, a four to five hour lag phase occurs and then growth is resumed at a reduced rate.
    • During the lag phase, the expression of around 13 proteins, which contain cold shock domains is increased two- to ten-fold.
    • Bacterial growth in batch culture can be modeled with four different phases: (A) the lag phase, when the population stays roughly the same; (B) the exponential, or log, phase, when the population grows at an increasing rate; (C) the stationary phase, when population growth stagnates; and (D) the death phase, when bacteria begin to die off and the population decreases in size.
    • Describe how the growth of bacteria is affected by temperature and how bacterial growth can be measured