6.2.1 Cloning and Biotechnology 119
(questions) Correctly Solved|2024
***Make a flow chart to show how you would calculate the affect of a factor on bacterial growth using
serial dilutions and agar plating - ✔ ✔ set up series of cultures identical in every way
EXCEPT for factor you are investigating e.g., temperature, presence of a nutrient or antibiotic
etc>culture for several days>for each culture carry out a serial dilution>plate each dilution, making
streaks on agar plate with sterile inoculating loop and label carefully to show which original culture it
has come from and what dilution factor is>repeat for all original cultures>culture agar plates for 5
days at 20°C>for each factor find plate with number of bacterial colonies that can be counted. Work out
original number of bacteria using dilution factor>compare results across different cultures to see effect
on bacterial growth of factor being investigated
Bioreactors may run batch or continueous processes. what is the difference? - ✔ ✔ 1. Continuous
processes run continuously once fermentation is started
2. sterile nutrient medium
added continuously once culture is growing exponentially
3. culture broth continually removed so
product can be processed and culture volume remains the same
4. Batch process everything added
at beginning in fixed volume of medium
5. nutrients used up and microorganisms, products, and waste products build up
6. may be stationary phase when secondary metabolites formed, process stopped, products extracted,
reactor cleaned, and new process begun
Compare the advantages and disadvantages of batch and continuous culture. - ✔ ✔ 1. Growth rate-
a) Batch- decreases as time goes on as nutrients become limiting factor and have to have lag phase each
time b) Continuous- even growth rate as always enough nutrients and only have one lag phase 2. Ease of
setup/ maintenance- a) Batch- easy to maintain b) Continuous- more difficult to maintain 3.
Consequence of contamination- a) Batch- Only messes up one batch b) Messes up the large volumes.
Cost to unplanned restarting of whole culture 4. Efficiency (rate of production)- a) Batch- less efficient,
,fermenter not in use at all time b) Continuous- More efficient, continuous operation 5. Good for
secondary or primary metabolites a) Batch- secondary b) Continuous- primary
Compare the process of culturing bacteria in broth and agar - ✔ ✔ 1. Both provide nutrients, suitable
pH, moisture etc
2. both need to be maintained at optimum
temperature for growth
3. both must be kept sterile until inoculated with microorganisms
4. both can be shaken at intervals to aerate it 5. agar plates remain closed once made up
6. broth is mixed with known volumes of culture medium
7. agar plates inoculated using sterile wire loop and culture
medium
8. numbers in broth counted using turbidity, serial dilutions, and microscope graticules
9. numbers on agar calculated using colony counting
Compare the way yeast is used in the process of baking and brewing - ✔ ✔ Baking:
1. Mixed with sugar and water
2. respires aerobically
3. carbon dioxide produced used to
make bread rise
4. yeast killed by heating as bread cooks (1); takes a couple of hours
Brewing:
1. mixed with malted barley and hot water
2. respiration (fermentation ) continues for days in anaerobic conditions
3. ethanol produced as waste product
4. yeast eventually inhibited (not killed) by rising pH
5. build-up of ethanol and lack of oxygen
Define agriculture - ✔ ✔ The science or practice of farming, including cultivation of the soil for the
growing of crops and the rearing of animals to provide food, wool, and other products
, Define asepsis - ✔ ✔ The absence of unwanted bacteria, viruses, and other microorganisms.
Define aseptic techniques - ✔ ✔ Techniques used to culture microorganisms in sterile conditions so
they are not contaminated with unwanted microorganisms
Define batch fermentation - ✔ ✔ 1. An industrial fermentation that runs for a set time
2. The microorganisms are inoculated into a fixed volume of medium
3. As growth takes place, nutrients are used up and both new biomass and waste products build up
4. As the culture reaches the stationary phase, overall growth ceases but during this phase the
microorganisms often carry out biochemical changes to form the desired end products
5. The process is stopped before the death phase and the products harvested. The whole system is
cleaned, sterilised and a new batch culture set up
Define biotechnology and give 3 examples - ✔ ✔ 1. Biotechnology involves applying biological
organisms or enzymes to the synthesis, breakdown or transformation of materials in the service of
people in chemical or industrial processes
2. Production of food e.g. yogurt, cheese, beer
3. DNA manipulation to produce genetically engineered microorganisms synthesising drugs such as
insulin and antibiotics
4. Bio-remediation- use of biological systems to remove soil and water pollutants
Define callus - ✔ ✔ A mass of undifferentiated plant cells that has been grown from an explant.
Define contaminant - ✔ ✔ Any unwanted microorganism
Define continuous fermentation - ✔ ✔ 1. An industrial fermentation where culture broth is removed
continuously and more nutrient medium is added
2. Microorganisms are inoculated into sterile nutrient medium and start to grow
3. Sterile nutrient medium is added continually to the culture once it reaches the exponential point of
growth
4. Culture broth is continually removed- the medium, waste products, microorganisms and product-
keeping the culture volume in the bioreactor constant.
Define culture - ✔ ✔ Growing living matter in vitro, for example, microorganisms in specifically
prepared nutrient medium
(questions) Correctly Solved|2024
***Make a flow chart to show how you would calculate the affect of a factor on bacterial growth using
serial dilutions and agar plating - ✔ ✔ set up series of cultures identical in every way
EXCEPT for factor you are investigating e.g., temperature, presence of a nutrient or antibiotic
etc>culture for several days>for each culture carry out a serial dilution>plate each dilution, making
streaks on agar plate with sterile inoculating loop and label carefully to show which original culture it
has come from and what dilution factor is>repeat for all original cultures>culture agar plates for 5
days at 20°C>for each factor find plate with number of bacterial colonies that can be counted. Work out
original number of bacteria using dilution factor>compare results across different cultures to see effect
on bacterial growth of factor being investigated
Bioreactors may run batch or continueous processes. what is the difference? - ✔ ✔ 1. Continuous
processes run continuously once fermentation is started
2. sterile nutrient medium
added continuously once culture is growing exponentially
3. culture broth continually removed so
product can be processed and culture volume remains the same
4. Batch process everything added
at beginning in fixed volume of medium
5. nutrients used up and microorganisms, products, and waste products build up
6. may be stationary phase when secondary metabolites formed, process stopped, products extracted,
reactor cleaned, and new process begun
Compare the advantages and disadvantages of batch and continuous culture. - ✔ ✔ 1. Growth rate-
a) Batch- decreases as time goes on as nutrients become limiting factor and have to have lag phase each
time b) Continuous- even growth rate as always enough nutrients and only have one lag phase 2. Ease of
setup/ maintenance- a) Batch- easy to maintain b) Continuous- more difficult to maintain 3.
Consequence of contamination- a) Batch- Only messes up one batch b) Messes up the large volumes.
Cost to unplanned restarting of whole culture 4. Efficiency (rate of production)- a) Batch- less efficient,
,fermenter not in use at all time b) Continuous- More efficient, continuous operation 5. Good for
secondary or primary metabolites a) Batch- secondary b) Continuous- primary
Compare the process of culturing bacteria in broth and agar - ✔ ✔ 1. Both provide nutrients, suitable
pH, moisture etc
2. both need to be maintained at optimum
temperature for growth
3. both must be kept sterile until inoculated with microorganisms
4. both can be shaken at intervals to aerate it 5. agar plates remain closed once made up
6. broth is mixed with known volumes of culture medium
7. agar plates inoculated using sterile wire loop and culture
medium
8. numbers in broth counted using turbidity, serial dilutions, and microscope graticules
9. numbers on agar calculated using colony counting
Compare the way yeast is used in the process of baking and brewing - ✔ ✔ Baking:
1. Mixed with sugar and water
2. respires aerobically
3. carbon dioxide produced used to
make bread rise
4. yeast killed by heating as bread cooks (1); takes a couple of hours
Brewing:
1. mixed with malted barley and hot water
2. respiration (fermentation ) continues for days in anaerobic conditions
3. ethanol produced as waste product
4. yeast eventually inhibited (not killed) by rising pH
5. build-up of ethanol and lack of oxygen
Define agriculture - ✔ ✔ The science or practice of farming, including cultivation of the soil for the
growing of crops and the rearing of animals to provide food, wool, and other products
, Define asepsis - ✔ ✔ The absence of unwanted bacteria, viruses, and other microorganisms.
Define aseptic techniques - ✔ ✔ Techniques used to culture microorganisms in sterile conditions so
they are not contaminated with unwanted microorganisms
Define batch fermentation - ✔ ✔ 1. An industrial fermentation that runs for a set time
2. The microorganisms are inoculated into a fixed volume of medium
3. As growth takes place, nutrients are used up and both new biomass and waste products build up
4. As the culture reaches the stationary phase, overall growth ceases but during this phase the
microorganisms often carry out biochemical changes to form the desired end products
5. The process is stopped before the death phase and the products harvested. The whole system is
cleaned, sterilised and a new batch culture set up
Define biotechnology and give 3 examples - ✔ ✔ 1. Biotechnology involves applying biological
organisms or enzymes to the synthesis, breakdown or transformation of materials in the service of
people in chemical or industrial processes
2. Production of food e.g. yogurt, cheese, beer
3. DNA manipulation to produce genetically engineered microorganisms synthesising drugs such as
insulin and antibiotics
4. Bio-remediation- use of biological systems to remove soil and water pollutants
Define callus - ✔ ✔ A mass of undifferentiated plant cells that has been grown from an explant.
Define contaminant - ✔ ✔ Any unwanted microorganism
Define continuous fermentation - ✔ ✔ 1. An industrial fermentation where culture broth is removed
continuously and more nutrient medium is added
2. Microorganisms are inoculated into sterile nutrient medium and start to grow
3. Sterile nutrient medium is added continually to the culture once it reaches the exponential point of
growth
4. Culture broth is continually removed- the medium, waste products, microorganisms and product-
keeping the culture volume in the bioreactor constant.
Define culture - ✔ ✔ Growing living matter in vitro, for example, microorganisms in specifically
prepared nutrient medium
