Fill in the following blanks with suitable words :
Crop plants require a lot of nitrogen to make …………..

Answer

**Step-by-Step Solution:**

1. **Understanding the Requirement**: Crop plants require nitrogen for various essential functions. One of the primary roles of nitrogen in plants is related to the synthesis of important biological molecules.

2. **Identifying the Key Molecule**: The main biological molecules that require nitrogen are proteins. Proteins are crucial for plant growth and development, and they are made up of amino acids, which contain nitrogen.

3. **Filling in the Blank**: Given that crop plants require nitrogen to make proteins, we can fill in the blank in the statement: "Crop plants require a lot of nitrogen to make **proteins**."

4. **Conclusion**: Therefore, the complete statement is: "Crop plants require a lot of nitrogen to make proteins."

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