1. The concept of putting microbes to help clean up the environment is called

A. pasteurization
B. bioremediation
C. fermentation
D. biolistics

2. Which of the following is not employed as an oxidation method?

A. Oxidation ponds
B. Trickling filters
C. Contact aerators
D. All of these

3. The filtering medium of trickling filters is coated with microbial flora, known as

A. zoological film
B. geological film
C. zoological film
D. none of these

4. Some cyanobacteria produce potent neurotoxins that, if ingested, will kill humans. These cyanobacteria are most likely to contaminate

A. water rich in organic carbon wastes but poor in phosphate
B. water that are anoxic
C. water rich in phosphate wastes but poor in organic carbon
D. none of the above

5. The biogas production process takes place at the temperature

A. lesser than 25°C
B. 25-40°C
C. 45-60°C
D. all of these