1 markWhich of the following is a reason yeast is used to make bread?
Yeast is used to make bread because...
... it produces ethanol.
... it produces lactic acid.
... it produces carbon dioxide.
... it produces oxygen.
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1 markWhat is the name of the enzyme used to produce clear apple juice?
Lipase
Amylase
Protease
Pectinase
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1 markWhy are bacteria used in biotechnology?
They can make complex molecules.
They are found inside the human body.
They reproduce slowly.
They can become resistant to antibiotics.
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Bacteria are involved in the manufacture of which product?
alcohol
bread
yoghurt
penicillin
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1 markWhich of the following combinations of nutrients would be needed in a batch fermenter in the production of penicillin?
Amino acids and lipids
Lipids and glucose
Chlorine and amino acids
Glucose and amino acids
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1 markWhich products of fermentation (anaerobic respiration in yeast) are important in the production of beer and bread?
| beer | bread | |
| A | ethanol | simple sugars |
| B | lactic acid | ethanol |
| C | ethanol | carbon dioxide |
| D | simple sugars | lactic acid |
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1 markPenicillin is produced in a fermenter by growing the fungus Penicillium.
The graph below shows how the mass of living Penicillium fungus, and the concentration of penicillin, changed over time.
Which day would be the best to harvest the penicillin at?
3 days
1.5 days
5 days
3.5 days
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1 markWhich food shown in the graph below has the highest percentage stain removal with a biological washing powder?
Salad dressing
Chocolate pudding
Chocolate milkshake
Raspberry smoothie
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1 markThe following statements describe biofuel.
Which of these statements could be considered an advantage of biofuel?
1, 2 and 4
2 and 3 only
2 only
2 and 4 only
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1 markIndustrial fermenters are used to produce large quantities of microorganisms which can be used for many biotechnological processes.
Which of the following correctly matches the different conditions in the fermenters and the reason why it is important to control these conditions?
| aseptic conditions | optimum pH | agitation | |
| A | creates an even distribution of substances throughout the fermenter | prevents enzymes from denaturing so that enzyme activity is at a maximum | ensures that only the desired species of microorganisms grow in the fermenter |
| B | ensures that only the desired species of microorganisms grow in the fermenter | creates an even distribution of substances throughout the fermenter | prevents enzymes from denaturing so that enzyme activity is at a maximum |
| C | prevents enzymes from denaturing so that enzyme activity is at a maximum | ensures that only the desired species of microorganisms grow in the fermenter | creates an even distribution of substances throughout the fermenter |
| D | ensures that only the desired species of microorganisms grow in the fermenter | prevents enzymes from denaturing so that enzyme activity is at a maximum | creates an even distribution of substances throughout the fermenter |
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