Chapter 10: Soil Microbiology — Online MCQ Test
MICROBIOLOGY · CLASS 11th · Tamil Nadu State Board
Practice Chapter 10: Soil Microbiology with a free chapter-wise online MCQ test.
This chapter covers: Focusing on soil ecology this chapter examines soil microflora nutrient cycling nitrogen carbon sulfur phosphorus cycles and rhizosphere interactions. Students study mycorrhizae bi....
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter 10: Soil Microbiology — Important Questions & Answers
Which component of the soil serves as the primary reservoir for soil microorganisms?
- A. Humus
- B. Inorganic salts
- C. Pebbles
- D. Bedrock
Answer: A. Humus
Humus is the organic portion of soil that provides essential nutrients and surface area for microbial colonization.
Humus is the organic portion of soil that provides essential nutrients and surface area for microbial colonization.
The zone of soil immediately surrounding the plant root system is known as the:
- A. Lithosphere
- B. Rhizosphere
- C. Atmosphere
- D. Hydrosphere
Answer: B. Rhizosphere
The rhizosphere is the narrow region of soil that is directly influenced by root secretions and associated soil microorganisms.
The rhizosphere is the narrow region of soil that is directly influenced by root secretions and associated soil microorganisms.
Which process involves the conversion of ammonia into nitrates by soil bacteria?
- A. Nitrogen fixation
- B. Denitrification
- C. Nitrification
- D. Ammonification
Answer: C. Nitrification
Nitrification is the biological oxidation of ammonia to nitrite followed by the oxidation of nitrite to nitrate.
Nitrification is the biological oxidation of ammonia to nitrite followed by the oxidation of nitrite to nitrate.
Compare VAM (Vesicular-Arbuscular Mycorrhizae) and Ectomycorrhizae: which is true?
- A. VAM fungi penetrate the cortical cell walls, while Ectomycorrhizae form a sheath around the root
- B. Both are strictly pathogenic to the plants
- C. Ectomycorrhizae are found in 90% of all plants, while VAM is rare
- D. VAM fungi produce large visible mushrooms on the surface
Answer: A. VAM fungi penetrate the cortical cell walls, while Ectomycorrhizae form a sheath around the root
Endomycorrhizae (VAM) penetrate root cells, whereas ectomycorrhizae typically wrap around the exterior of the root tips.
Endomycorrhizae (VAM) penetrate root cells, whereas ectomycorrhizae typically wrap around the exterior of the root tips.
Which bio-agent is specifically recommended to solubilize phosphorus in soil?
- A. Pseudomonas fluorescens
- B. Bacillus megaterium
- C. Rhizobium leguminosarum
- D. Frankia
Answer: B. Bacillus megaterium
Bacillus megaterium is a well-known phosphate-solubilizing bacterium (PSB) that converts insoluble forms of phosphorus into available orthophosphates.
Bacillus megaterium is a well-known phosphate-solubilizing bacterium (PSB) that converts insoluble forms of phosphorus into available orthophosphates.