[Campbell Biology P.855] Which of the following statements accurately describe the interacti... | Practice Question

Which of the following statements accurately describe the interaction between soil particles, ions, and plant nutrient availability?

  • A: Negatively charged soil particles readily bind to anions like nitrate (NO3⁻), preventing their loss by leaching.
  • B: Positively charged ions (cations) such as K⁺ and Ca²⁺ adhere to negatively charged soil particles, making them less prone to leaching.
  • C: Roots absorb mineral cations directly from the surface of soil particles through passive diffusion.
  • D: A higher content of clay and organic matter generally increases a soil's capacity for cation exchange.
  • E: Cation exchange involves the displacement of cations from soil particles by other cations, notably H⁺.

Explanation

Option B is correct: Cations adhere to negatively charged soil particles, reducing leaching. Option D is correct: The text states that 'the more clay and organic matter in the soil, the higher the capacity to exchange cations'. Option E is correct: Cation exchange is defined as a process where 'cations are displaced from soil particles by other cations, particularly H+'. Options A and C are incorrect as negatively charged soil particles do not bind anions, and roots absorb cations from the soil solution via cation exchange, not directly from particles by passive diffusion.