use of biological resources

Question 1

what temperature is the milk pasteurised at and for how long when making yogurt

Answer 1

72 degrees
15 seconds - to kill any harmful microorganisms

Question 2

what bacteria is added to milk when making yogurt

Answer 2

lactobacillus

Question 3

what happens after lactobacillus is added to the milk

Answer 3

the mixture is incubated at 40-45 degrees - where the bacteria ferments the lactose in the milk
the bacteria converts the lactose into lactic acid which sours and thickens the milk - making yogurt

Question 4

after the yogurt has formed, what are the last two steps of yogurt making

Answer 4

the yogurt is stirred and cooled, halting the action of lactobacillus bacteria
flavourings, colourants may be added before packaging

Question 5

which type of respiration does lactobacillus use in the process of making yogurt

Answer 5

anaerobic respiration
uses lactose in milk as substrate

Question 6

why does the equipment get sterilised before the process of yogurt making

Answer 6

to kill any unwanted microorganisms
to prevent chemical contamination

Question 7

what does a pH probe do during industrial fermentation

Answer 7

controls pH during the process.
optimum pH keeps enzymes working efficiently - high rate of reaction

Question 8

what does a temperature probe do during industrial fermentation

Answer 8

monitors the temperature within fermenter
keeps it at optimum level for enzymes so they don’t denature but have a high rate of reaction

Question 9

what does a water cooled jacket do during industrial fermentation

Answer 9

surrounds vessel and helps control the temperature inside the vessel

Question 10

what does an air pump do during industrial fermentation

Answer 10

introduces air into the fermenter
which is crucial for aerobic fermentation - microorganisms require oxygen to respire

Question 11

what is the primary focus of industrial fermentation

Answer 11

using microorganisms to transform raw materials into valuable products

Question 12

why are paddles used in industrial fermentation

Answer 12

to mix and distribute nutrients

Question 13

what are the drawbacks of selective breeding

Answer 13

it reduces the size of the gene pool
the population as a whole will be more at risk of disease
rare inherited diseases are more likely to appear - inbreeding