With refernce to human repiration which is correct ?

Options

A. pulmonary ventialtion is equal to alveolar ventilation
B. alveolar ventialtion is more than pulmonary ventialtin
C. pulmonayr ventialtion is less than alveolar ventialtion
D. alveolar ventialtions is less than pulmonary ventialation

Answer

To solve the question regarding human respiration, we need to understand the concepts of pulmonary ventilation and alveolar ventilation. Here’s a step-by-step breakdown of the solution:

### Step 1: Define Pulmonary Ventilation
Pulmonary ventilation refers to the total volume of air that is inhaled and exhaled from the lungs in a given period. It is calculated as:
\[ \text{Pulmonary Ventilation} = \text{Tidal Volume} \times \text{Respiratory Rate} \]
In humans, the tidal volume (the amount of air inhaled or exhaled in one breath) is approximately 500 ml, and the average respiratory rate is about 15 to 16 breaths per minute.

### Step 2: Calculate Pulmonary Ventilation
Using the values provided:
\[ \text{Pulmonary Ventilation} = 500 \, \text{ml} \times 15 \, \text{(average respiratory rate)} = 7500 \, \text{ml/min} \]

### Step 3: Define Alveolar Ventilation
Alveolar ventilation is the volume of air that reaches the alveoli (the sites of gas exchange) and is available for gas exchange. It accounts for the dead space (the volume of air that does not participate in gas exchange). The dead space is approximately 150 ml in humans.

### Step 4: Calculate Alveolar Ventilation
To find alveolar ventilation, we subtract the dead space from the tidal volume:
\[ \text{Alveolar Ventilation} = (\text{Tidal Volume} - \text{Dead Space}) \times \text{Respiratory Rate} \]
\[ \text{Alveolar Ventilation} = (500 \, \text{ml} - 150 \, \text{ml}) \times 15 \]
\[ \text{Alveolar Ventilation} = 350 \, \text{ml} \times 15 = 5250 \, \text{ml/min} \]

### Step 5: Compare Pulmonary and Alveolar Ventilation
From the calculations:
- Pulmonary Ventilation = 7500 ml/min
- Alveolar Ventilation = 5250 ml/min

### Conclusion
Since pulmonary ventilation is greater than alveolar ventilation, we can conclude that:
**Alveolar ventilation is less than pulmonary ventilation.**

### Final Answer
The correct statement regarding human respiration is: **Alveolar ventilation is less than pulmonary ventilation.**

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