MCQ Detailed View

For healthy growth and development, plants require several nutrients, but three primary macronutrients are essential and needed in large amounts: Nitrogen (N), Phosphorus (P), and Potassium (K). These three elements are commonly referred to as NPK and are the main components of most fertilizers used in agriculture.

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   Nitrogen (N):

   
   
   
   
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     Nitrogen is a key part of chlorophyll, the pigment responsible for photosynthesis.

     
     
   
   
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     It is also a major component of amino acids, proteins, nucleic acids (DNA/RNA), and enzymes that control plant growth.

     
     
   
   
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     Plants deficient in nitrogen show stunted growth and yellowing leaves due to poor chlorophyll formation.

     
     
   
   
   
   


2. 
   

   Phosphorus (P):

   
   
   
   
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     Phosphorus plays a crucial role in energy transfer within the plant through compounds like ATP (adenosine triphosphate).

     
     
   
   
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     It supports root development, flowering, fruit formation, and overall energy metabolism.

     
     
   
   
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     A lack of phosphorus causes weak root systems and poor seed production.

     
     
   
   
   
   


3. 
   

   Potassium (K):

   
   
   
   
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     Potassium is vital for regulating water balance, enzyme activation, and carbohydrate synthesis in plants.

     
     
   
   
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     It strengthens plant stems, improves disease resistance, and enhances flower and fruit quality.

     
     
   
   
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     Potassium deficiency leads to brown leaf edges, weak stalks, and reduced yield.

     
     
   
   
   
   

Other elements like carbon (C), sulfur (S), calcium (Ca), and magnesium (Mg) are also important but are either derived from air/water or needed in smaller quantities compared to NPK. That is why fertilizers are labeled with N-P-K values to indicate their nutrient composition.Thus, the three primary nutrients needed for healthy plant growth are Nitrogen (N), Phosphorus (P), and Potassium (K), making option N, P, K the correct answer.