After forceful inspiration, the amount of air that can be breathed out by maximum forced expiration is equal to

Options

A. inspiratory reserve voume (irv) + expiratory reserve voume (erv)+ tidal volume (tv) + residual volume (rv)
B. irv+rv+erv
C. irv+tv+erv
D. tv+rv+erv

Answer

To solve the question, "After forceful inspiration, the amount of air that can be breathed out by maximum forced expiration is equal to," we need to understand the different lung volumes involved in breathing.

### Step-by-Step Solution:

1. **Identify the Key Terms**:
- **Inspiratory Reserve Volume (IRV)**: The maximum volume of air that can be inhaled after a normal inhalation.
- **Expiratory Reserve Volume (ERV)**: The maximum volume of air that can be exhaled after a normal exhalation.
- **Tidal Volume (TV)**: The volume of air inhaled or exhaled during normal breathing at rest.
- **Residual Volume (RV)**: The amount of air remaining in the lungs after a full exhalation.

2. **Understanding the Question**:
- The question asks for the amount of air that can be breathed out after a forceful inspiration. This is essentially asking for the total volume of air that can be exhaled after taking a deep breath.

3. **Concept of Vital Capacity**:
- The total amount of air that can be forcibly exhaled after a maximum inhalation is known as **Vital Capacity (VC)**.
- Vital Capacity is calculated as:
\[ VC = IRV + ERV + TV \]
- This means that after a forceful inspiration, the maximum amount of air that can be exhaled is equal to the sum of the Inspiratory Reserve Volume, Expiratory Reserve Volume, and Tidal Volume.

4. **Conclusion**:
- Therefore, the correct answer to the question is:
\[ \text{IRV + ERV + TV} \]
- This indicates that after forceful inspiration, the amount of air that can be breathed out by maximum forced expiration is equal to the sum of Inspiratory Reserve Volume, Expiratory Reserve Volume, and Tidal Volume.

### Final Answer:
The amount of air that can be breathed out by maximum forced expiration after forceful inspiration is equal to **Inspiratory Reserve Volume (IRV) + Expiratory Reserve Volume (ERV) + Tidal Volume (TV)**.

---