Dead space is

Options

A. respiratory tract
B. nasal chambers only
C. alveolar space
D. pleural cavity

Answer

**Step-by-Step Solution:**

1. **Understanding Dead Space**: Dead space refers to the volume of air that is inhaled but does not participate in gas exchange. It is important to differentiate between the air that is involved in the exchange of gases and the air that is not.

2. **Identifying Locations of Dead Space**:
- **Conducting Airways**: This includes parts of the respiratory tract such as the trachea and bronchi, where air is conducted but not exchanged.
- **Alveolar Space**: Sometimes, air reaches the alveoli, but if those alveoli are poorly perfused or not functional, the air does not participate in gas exchange.

3. **Conclusion**: Dead space can be found in the conducting airways and in poorly perfused alveoli. It is the volume of air that does not contribute to the exchange of oxygen and carbon dioxide.

4. **Final Definition**: Dead space is the volume of air that is inhaled but does not take part in the gas exchange process, either because it is trapped in the conducting airways or because it reaches non-functional alveoli.

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