Ribosomes are the sites of .......... Synthesis.

Explanation

**Step-by-Step Solution:**

1. **Understanding Ribosomes**: Ribosomes are cellular structures that play a crucial role in the synthesis of proteins. They can be found either floating freely in the cytoplasm or attached to the endoplasmic reticulum (ER).

2. **Types of Ribosomes**: There are two main types of ribosomes based on their size: 70S ribosomes (found in prokaryotes) and 80S ribosomes (found in eukaryotes).

3. **Function of Ribosomes**: The primary function of ribosomes is to facilitate the process of translation, where messenger RNA (mRNA) is decoded to build proteins. This process involves linking amino acids together in a specific sequence to form a protein.

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