Microbial Growth and Genetics PPT
- Individual growth = a single cell gets bigger
- Population growth (reproduction) = organisms make copies of themselves
Prokaryotes —> Asexual reproduction —> Binary fission is also called
transverse fission because single cells divide across their width
-Chromosome replicates within a cell
-Chromosomes move to opposite sides of the cell
-Protein band forms down the middle of the cell
-Septum formation begins
- Growth —> every time a cell goes through binary fission, the population growth
doubles (doubling time) and is very predictable—> exponential growth curve
Nf = ( Ni ) 2 ^ n
Nf = total population
Ni = initial amount in population
n = number of generations
Doubling/generation time varies between bacterial species (minutes to months)
- Static cultures = environment that doesn’t change over time (ie. Growing bacteria in a
lab and not changing agar plates, letting waste build up, etc)
Growth curve goes through stages
Lag Phase — bacteria have to get used to surroundings when first
inoculated, growth is slow
Exponential Growth Phase — all bacteria young and healthy and plenty
of food, live cells > dead cells (waste products)
Stationary Phase — food becomes more scarce, bacteria start dying and
contribute to metabolic waste build up, live cells = dead cells
Death Phase— nutrients run out, waste build up effecting young cells, live
cells < dead cells
- Individual growth = a single cell gets bigger
- Population growth (reproduction) = organisms make copies of themselves
Prokaryotes —> Asexual reproduction —> Binary fission is also called
transverse fission because single cells divide across their width
-Chromosome replicates within a cell
-Chromosomes move to opposite sides of the cell
-Protein band forms down the middle of the cell
-Septum formation begins
- Growth —> every time a cell goes through binary fission, the population growth
doubles (doubling time) and is very predictable—> exponential growth curve
Nf = ( Ni ) 2 ^ n
Nf = total population
Ni = initial amount in population
n = number of generations
Doubling/generation time varies between bacterial species (minutes to months)
- Static cultures = environment that doesn’t change over time (ie. Growing bacteria in a
lab and not changing agar plates, letting waste build up, etc)
Growth curve goes through stages
Lag Phase — bacteria have to get used to surroundings when first
inoculated, growth is slow
Exponential Growth Phase — all bacteria young and healthy and plenty
of food, live cells > dead cells (waste products)
Stationary Phase — food becomes more scarce, bacteria start dying and
contribute to metabolic waste build up, live cells = dead cells
Death Phase— nutrients run out, waste build up effecting young cells, live
cells < dead cells
