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Question 23M.3.SL.TZ1.11

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Date May 2023 Marks available [Maximum mark: 4] Reference code 23M.3.SL.TZ1.11
Level SL Paper 3 Time zone TZ1
Command term Explain Question number 11 Adapted from N/A
11.
[Maximum mark: 4]
23M.3.SL.TZ1.11

Microorganisms are used in industry for making a range of products. Explain the reasons that conditions must be carefully controlled inside fermenters for optimal production.

[4]

Markscheme
  1. carbon dioxide from respiration lowers the pH;
  2. affecting enzyme activity of microorganisms;
  3. low oxygen availability will stop aerobic respiration;
  4. heat generation (by metabolism) raises the temperature, which may denature enzymes;
  5. gas production may build up pressure and affect rates of reaction;
  6. nutrient level /mixing needed for production;
  7. build-up of waste product/toxins may harm microorganisms;
  8. contaminant microorganisms may outcompete useful microbial population;
Examiners report

If this was answered, there were rarely explanations given for conditions., just a list of conditions such as temperature, pH etc.