Answer: Penicillium notatum.
- A Aspergillus niger
- B Trichoderma polysporum
- C Penicillium notatum
- D Monascus purpureus
Correct answer: C. Penicillium notatum
Explanation: Penicillin was discovered by Alexander Fleming from Penicillium notatum (now also produced from Penicillium chrysogenum).
Sewage passes through physical removal (primary), then aerobic biological treatment where microbes form flocs that consume organic matter (secondary); the settled activated sludge is then digested anaerobically to produce biogas - a deliberate switch from aerobic to anaerobic conditions between stages.
Concept context
Microorganisms in food, medicine, sewage treatment, biocontrol, and biofertilizers