how much amount of volume of air is in lungs FRC

Options

A. 1500 ml to 1600 ml
B. 2100 ml to 2500 ml
C. 2500 ml to 3000 ml
D. 1600 ml to 2100 ml

Answer

To find the volume of air in the lungs during Functional Residual Capacity (FRC), we need to understand the components that make up FRC. Here’s a step-by-step solution:

### Step 1: Define Functional Residual Capacity (FRC)
FRC is the volume of air remaining in the lungs after a normal expiration. It is a combination of two volumes: Expiratory Reserve Volume (ERV) and Residual Volume (RV).

### Step 2: Understand Expiratory Reserve Volume (ERV)
ERV is the amount of air that can be forcibly exhaled after a normal expiration. The typical volume of ERV ranges from 1000 ml to 1100 ml.

### Step 3: Understand Residual Volume (RV)
RV is the amount of air that remains in the lungs after a forcible expiration. The typical volume of RV ranges from 1100 ml to 1200 ml.

### Step 4: Calculate FRC
To find FRC, we add ERV and RV together:
- **FRC = ERV + RV**
- Using the average values:
- ERV = 1000 ml (average)
- RV = 1150 ml (average)

So,
- **FRC = 1000 ml + 1150 ml = 2150 ml**

### Step 5: State the Range of FRC
Based on the ranges provided:
- ERV can range from 1000 ml to 1100 ml
- RV can range from 1100 ml to 1200 ml

Thus, the total FRC can range from:
- Minimum: 1000 ml + 1100 ml = 2100 ml
- Maximum: 1100 ml + 1200 ml = 2300 ml

### Conclusion
The volume of air in the lungs during FRC is approximately between 2100 ml to 2300 ml.