The difference between maximum and resting cardiac output of a person is called

Options

A. stroke volume
B. reserve volume
C. cardiac reserve
D. residual volume

Answer

To solve the question regarding the difference between maximum and resting cardiac output of a person, let's follow these steps:

### Step-by-Step Solution:

1. **Understand Cardiac Output**:
- Cardiac output is the amount of blood the heart pumps in one minute. It is a critical measure of heart function.

2. **Define Resting Cardiac Output**:
- Resting cardiac output refers to the amount of blood pumped by the heart when a person is at rest. This is the baseline level of cardiac output.

3. **Define Maximum Cardiac Output**:
- Maximum cardiac output is the highest amount of blood the heart can pump in one minute during intense physical activity or stress.

4. **Calculate the Difference**:
- The difference between maximum cardiac output and resting cardiac output represents the additional capacity of the heart to increase blood flow during physical exertion.

5. **Identify the Term for This Difference**:
- The term that describes this difference is known as "cardiac reserve." Cardiac reserve indicates how much more blood the heart can pump beyond its resting level.

6. **Eliminate Incorrect Options**:
- Option A (Stroke Volume) refers to the amount of blood pumped with each heartbeat, not the difference between maximum and resting output.
- Option B (Reserve Volume) is related to respiratory physiology, not cardiac output.
- Option D (Residual Volume) pertains to the volume of air remaining in the lungs after maximum expiration, which is unrelated to cardiac output.

7. **Conclusion**:
- Based on the definitions and explanations, the correct answer to the question is **Cardiac Reserve**.

### Final Answer:
The difference between maximum and resting cardiac output of a person is called **Cardiac Reserve**.

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