amino acid : protein :: nucleotides : ……………

Explanation

To solve the analogy "amino acid : protein :: nucleotides : ……………", we will follow these steps:

### Step 1: Understand the relationship between the first pair (amino acid and protein).
- Amino acids are the basic building blocks (monomers) that combine to form proteins (polymers).

### Step 2: Identify what nucleotides are.
- Nucleotides are the basic building blocks (monomers) of nucleic acids.

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