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Monday, 22 June 2026
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Biology Past Questions and Answers

Biology Questions

Question 386:
Erosion can be reduced along shape by
  • A Ridging across slope
  • B Ridging up slope
  • C Ridging down slope
  • D Crop rotation
  • E Bush fallowing system
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Question 387:
If a handful of soil is shaken with water and left to settle, the soil particles will settle from light to heavy particles as follows
  • A Humus, clay, silt, sand, stones
  • B Humus, silt, clay, sand, stones
  • C Humus, clay,silt, stones, sand
  • D Humus, sand, silt, clay, stones
  • E Clay, humus, silt, sand, stones
View Answer & Explanation
Question 388:
Denitrifying bacteria in nature liberate gaseous nitrogen directly from
  • A Ammonium salts
  • B Soil nitrates
  • C Thunderstorms
  • D Soil nitrites
  • E Plant and animal proteins
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Question 389:
Leaching is
  • A Washing away of humus from the soil surface
  • B Reducing of soil aeration by pressure
  • C Soil erosion by means other than rainfall
  • D Loss of organic matter due to exposure to direct sunlight
  • E Washing out chalk and limestone from upper layers of by heavy rains
View Answer & Explanation
Question 390:
The process of soil erosion is usually from
  • A Rill → sheet → gully
  • B Gully → rill → sheet
  • C Sheet → guly → rill
  • D Sheet → rill → gully
  • E Rill → gully → sheet
View Answer & Explanation