All Free Agriculture MCQs with Answers

Every Agriculture question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.

2,315 questions · page 104 of 116

  • A. Rain splash rill erosion
  • B. Stream bank erosion
  • C. Sheet erosion
  • D. Gully erosion

Explanation: Sheet erosion removes a relatively uniform thin layer of soil across the surface through flowing water.

Correct answer: Sheet erosion
  • A. 12.5 % -12.5 % - 75%
  • B. 64.7 % - 27.4 % - 7.9 %
  • C. none of A & B
  • D. 7.9% - 27.7 % - 64.4

Explanation: The commonly cited crustal proportions are approximately 64.7% igneous, 27.4% metamorphic, and 7.9% sedimentary rocks.

Correct answer: 64.7 % - 27.4 % - 7.9 %
  • A. 64 %
  • B. 79 %
  • C. 75 %
  • D. 73 %

Explanation: Oxygen makes up about 46.6% and silicon about 27.7% of the Earth’s crust by weight, giving a combined value near 74%, conventionally…

Correct answer: 75 %
  • A. 23 %
  • B. 2.3 %
  • C. 17 %
  • D. 1.7 %

Explanation: Potassium constitutes about 2.3% of the Earth’s crust by weight. The other percentage choices are much too high for potassium’s crustal…

Correct answer: 2.3 %
  • A. Provides energy for the microbial
  • B. Maintains the productivity of soil
  • C. Gives structure to the soil
  • D. All of these

Explanation: Soil organic matter feeds microorganisms, releases and stores nutrients, improves aggregation and structure, and supports long-term soil…

Correct answer: All of these
  • A. both A & B
  • B. Humic acid & Fulvic acid
  • C. Hymatomelanic acid & Humin
  • D. None of theseGeology

Explanation: Humic substances are commonly fractionated into fulvic acid, humic acid and humin; hymatomelanic acid is also recognised as a fraction of…

Correct answer: both A & B
  • A. Ca
  • B. N
  • C. Mg
  • D. None of the above

Explanation: Nitrogen is an essential part of amino acids and therefore proteins, and it forms the nitrogenous bases of nucleic acids.

Correct answer: N
  • A. An area of soil from root surface to 5 cm
  • B. Area within the roots
  • C. Root surface
  • D. All of them

Explanation: The rhizoplane is the actual root surface, including the immediate surface zone where roots interact with soil microorganisms.

Correct answer: Root surface
  • A. Composition of molten magma
  • B. Depth of molten magma
  • C. Both A and B
  • D. Composition can not be determined.

Explanation: The mineral composition of an igneous rock primarily reflects the chemical composition of the molten magma from which it crystallises.

Correct answer: Composition of molten magma
  • A. Gleization
  • B. The correct option is not present aboveHire Grant Writers
  • C. Laterization
  • D. Lessivage

Explanation: The general process of mixing soil horizons or soil materials is called pedoturbation, and that term is absent from the options.

Correct answer: The correct option is not present aboveHire Grant Writers
  • A. 74 %
  • B. 54 %
  • C. 62.5 %
  • D. 34%

Explanation: The Walkley-Black method oxidises only about 74 to 77 percent of the organic carbon, so a correction factor is commonly applied.

Correct answer: 74 %
  • A. 110 0C
  • B. 120 0C
  • C. both A and B
  • D. 105 0C

Explanation: For routine gravimetric soil moisture analysis, samples are commonly dried to constant weight at about 105°C.

Correct answer: 105 0C
  • A. Mollisols
  • B. Arable soils
  • C. Histosols
  • D. Non-arable soils

Explanation: Cultivation commonly removes or incorporates the surface organic layer, so a distinct O horizon is generally absent in arable soils.

Correct answer: Arable soils
  • A. Bacteria
  • B. both A & B
  • C. Fungi
  • D. None of the above

Explanation: Vesicular arbuscular mycorrhiza is a symbiotic association formed by fungi with plant roots.

Correct answer: Fungi
  • A. Plasma
  • B. Quartz
  • C. Carbon
  • D. None of these

Explanation: ICP-AES uses an inductively coupled plasma, usually an argon plasma, to reach the extreme temperatures needed to excite atoms and produce…

Correct answer: Plasma
  • A. 20 mg of ca2+
  • B. All of the above
  • C. 9 mg of Al3+
  • D. 12 mg of Mg2+

Explanation: Equivalent amounts are calculated using atomic or molecular mass divided by valency: Ca²⁺ is about 20 mg, Mg²⁺ about 12 mg, and Al³⁺ about…

Correct answer: All of the above
  • A. Aristotle et al.
  • B. Hiltner
  • C. A.Q khan
  • D. Helium. S. Denial

Explanation: Lorenz Hiltner introduced the term rhizosphere for the soil region influenced by plant roots.

Correct answer: Hiltner
  • A. Shafiq Khalil et al.
  • B. Theodore Saussure
  • C. Dr. Muhammad Sharif et al.
  • D. C. Sprengel

Explanation: C. Sprengel was among the first to establish the essential role of mineral elements such as potassium, calcium, magnesium and phosphorus…

Correct answer: C. Sprengel
  • A. Bacteria
  • B. Actinomycetes
  • C. Fungi
  • D. Both B & C

Explanation: Bacteria usually dominate the initial breakdown of easily decomposable compounds in fresh organic matter.

Correct answer: Bacteria
  • A. Ammonical
  • B. Both B & C
  • C. Ammonical-nitrate
  • D. Nitrate

Explanation: Nitrate nitrogen is prone to denitrification under flooded, anaerobic conditions, causing gaseous nitrogen losses.

Correct answer: Both B & C