Unit 6 Chapter 13: Microbes in Human Welfare — Online MCQ Test
BOTANY · CLASS 12 INTERMEDIATE 2 YEAR · Telangana State Board
Practice Unit 6 Chapter 13: Microbes in Human Welfare with a free chapter-wise online MCQ test.
This chapter covers: The final chapter examines beneficial roles of microorganisms in household products industrial production sewage treatment biogas generation biocontrol agents and biofertilizer app....
AI-generated questions from basic to board-exam level, with instant results and explanations.
Unit 6 Chapter 13: Microbes in Human Welfare — Important Questions & Answers
Which microorganism is used in the production of curd from milk?
- A. Lactobacillus
- B. Rhizobium
- C. Aspergillus
- D. Penicillium
Answer: A. Lactobacillus
Lactobacillus converts milk sugar into lactic acid, which helps in curd formation. It is a common beneficial bacterium used in household food preparation.
Lactobacillus converts milk sugar into lactic acid, which helps in curd formation. It is a common beneficial bacterium used in household food preparation.
Which of the following is used in the production of bread and alcoholic beverages?
- A. Bacteria
- B. Yeast
- C. Protozoa
- D. Algae
Answer: B. Yeast
Yeast, especially Saccharomyces cerevisiae, carries out fermentation and is used in baking and brewing. It produces carbon dioxide and alcohol during the process.
Yeast, especially Saccharomyces cerevisiae, carries out fermentation and is used in baking and brewing. It produces carbon dioxide and alcohol during the process.
In sewage treatment, the primary role of aerobic bacteria is to
- A. increase the amount of toxic gases
- B. reduce organic matter and BOD
- C. produce curd
- D. fix atmospheric nitrogen
Answer: B. reduce organic matter and BOD
Aerobic bacteria decompose organic waste in the sewage and reduce the biochemical oxygen demand (BOD). This makes the water less polluting.
Aerobic bacteria decompose organic waste in the sewage and reduce the biochemical oxygen demand (BOD). This makes the water less polluting.
In a sewage treatment plant, the flocs formed are mainly due to the activity of
- A. Bacterial masses and fungal hyphae
- B. Only algae
- C. Only viruses
- D. Only protozoa
Answer: A. Bacterial masses and fungal hyphae
Flocs are masses of bacteria associated with fungal filaments that help in decomposition of organic matter. These are central to secondary treatment of sewage.
Flocs are masses of bacteria associated with fungal filaments that help in decomposition of organic matter. These are central to secondary treatment of sewage.
Which of the following pairs is correctly matched?
- A. Rhizobium — phosphate solubilization
- B. Azotobacter — nitrogen fixation
- C. Bacillus thuringiensis — curd formation
- D. Aspergillus niger — biogas production
Answer: B. Azotobacter — nitrogen fixation
Azotobacter is a free-living nitrogen-fixing bacterium used as a biofertilizer. The other options are incorrect matches of microbe and function.
Azotobacter is a free-living nitrogen-fixing bacterium used as a biofertilizer. The other options are incorrect matches of microbe and function.