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Question 18M.3.SL.TZ1.c

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Date May 2018 Marks available [Maximum mark: 2] Reference code 18M.3.SL.TZ1.c
Level SL Paper 3 Time zone TZ1
Command term Distinguish Question number c Adapted from N/A
c.
[Maximum mark: 2]
18M.3.SL.TZ1.c

Citric acid is produced industrially from sugars in continuous fermenters using the fungus Aspergillus niger and with date syrup as a growth medium. Citric acid is a byproduct of the metabolism of this fungus. The fungus requires a nitrogen source for optimal growth and the impact of different nitrogen sources on citric acid production was investigated. The control received no additional nitrogen.

Citric acid can be produced by either batch fermentation or continuous fermentation. Distinguish between these two methods.

[2]

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