Biotechnology (Cambridge O Level Biology)

Industrial 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

Which 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

Penicillin 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?

Which food shown in the graph below has the highest percentage stain removal with a biological washing powder?