Cultivation Of Bacteria + Maths Flashcards
Why is batch culture (growing bacteria in flask) called a CLOSED CULTURE
No nutrients/toxic products or dead bacteria are removed from cultivation
What 6 conditions do bacteria need to grow
1- nutrients
2- optimal temp
3- ph
4- salinity (naCl conditions)
5- moisture/water
6- gas (02 or co2) : respiration
Why does bacteria need nutrients and gas
Because they use energy (from nutrients in metabolism) but also produce it via respiration
what are the 4 types of macronutrients which bacteria need for ion provision
1- proteins (provides N)
2- Lipids (provides C,O)
3- carbohydrates (provides C,O)
4- nucleic acids (provides N)
What are the 4 essential elements/micronutrients
1- carbon
2- oxygen
3- nitrogen ( synthesises dna)
4- phosphorus (synthesises new dna )
Which 2 types of media provide the nutrients needed
1- chemically DEFINED media
2- undefined COMPLEX media
What is chemically defined media
Media which gives compounds which directly produced micronutrients like N,C,O,P
Eg glucose
What is undefined complex media
Media which gives complex compound which breakdown into things like Lipids, carbs, proteins
Eg yeast extract
What 2 variables are needed to measure amount of bacteria
Population density per volume (optical density, turbidity)
Population number (ie plating, counting, flow cytometry)
Which technique is used to measure popn density
Optical density / turbidity
What are CFU counted in the plating method
Colony forming units
Why would you watch cell growth
To see if cells are healthy for division
How do you work out from log2 the generations of division
Eg given you have 32768 cells how many division
Log2(number) = divisions
Eg 2^0 = 0 division (1 cell)
2^1 = 2 divisions because log2(2) = 1
How do you work our generation time from a graph with time and number of bacteria plotted
G= total time / number of division (3.3 log b/B)
How do you work out number of divisions
Log(final number) - Log (initial)
/
Log(2) = 0.32
=3.3logb/B
