Physical process involving intake of `O_2` and release of `CO_2` is ________

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for a physical process that involves the intake of oxygen (O₂) and the release of carbon dioxide (CO₂).

2. **Identifying the Process**: The process of taking in oxygen is known as inhalation, while the process of expelling carbon dioxide is known as exhalation. Together, these two actions form a cycle.

3. **Defining the Overall Process**: The combination of inhalation and exhalation is referred to as "breathing." This is a physical process that occurs in both plants and animals.

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