when 1200 ml air is left in the lungs , it is called

Options

A. (1) tidal volume
B. (2) inspiratory reserve volume
C. 3) vital capacity
D. (4) residual volume

Answer

To answer the question "When 1200 ml of air is left in the lungs, it is called," we need to understand the different lung volumes and capacities. Here’s a step-by-step solution:

### Step 1: Understand Lung Volumes
Lung volumes are categorized into different types based on their function and the amount of air they contain. The main types include tidal volume, inspiratory reserve volume, expiratory reserve volume, vital capacity, and residual volume.

### Step 2: Define Each Volume
- **Tidal Volume (TV)**: This is the amount of air inhaled or exhaled during normal breathing. It is approximately 500 ml.
- **Inspiratory Reserve Volume (IRV)**: This is the additional air that can be inhaled after a normal inhalation, averaging between 2500 ml to 3000 ml.
- **Expiratory Reserve Volume (ERV)**: This is the additional air that can be exhaled after a normal exhalation.
- **Vital Capacity (VC)**: This is the maximum amount of air a person can exhale after a maximum inhalation. It includes tidal volume, inspiratory reserve volume, and expiratory reserve volume.
- **Residual Volume (RV)**: This is the volume of air remaining in the lungs after a forcible expiration. It typically averages between 1100 ml to 1200 ml.

### Step 3: Identify the Correct Volume
Given that the question states "1200 ml air is left in the lungs," we need to identify which lung volume corresponds to this amount. Since residual volume is defined as the air left in the lungs after a forcible expiration and averages around 1100 ml to 1200 ml, the correct answer is **Residual Volume**.

### Conclusion
The correct answer to the question is **Residual Volume**.

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