AP BIOLOGY

Detailed explanation-1: -Explanation: Soil is a major source of nutrients needed by plants for growth. The three main nutrients are nitrogen (N), phosphorus (P) and potassium (K). Together they make up the trio known as NPK.

Detailed explanation-2: -The primary nutrients are nitrogen, phosphorus and potassium. You may be most familiar with these three nutrients because they are required in larger quantities than other nutrients. These three elements form the basis of the N-P-K label on commercial fertilizer bags.

Detailed explanation-3: -Soil is one of the important components for plants because it contains nutrients and moisture necessary for plant growth (Kim et al.

Detailed explanation-4: -Roots are the primary source of soil organic matter. Dead roots and gelatinous materials exuded by living plant roots are decomposed by soil organisms and converted into organic matter.