Fill in the following blanks with suitable words:
In fishes, exchange of gases occur through …………………

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks us to fill in the blank regarding how fishes exchange gases.

2. **Identifying the Process**: The process of exchanging gases in organisms is known as respiration. In fishes, this involves taking in oxygen and releasing carbon dioxide.

3. **Recognizing the Structures Involved**: In fishes, the specialized structures responsible for gas exchange are called gills. These are vascularized structures that allow for efficient transfer of gases.

4. **Filling in the Blank**: Based on the information gathered, we can fill in the blank: "In fishes, exchange of gases occurs through **gills**."

**Final Answer**: In fishes, exchange of gases occurs through **gills**.

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