Cardiac output signifies

Options

A. The amount of blood entering the heart per unit time
B. The amount of blood entering the lung per unit time
C. The amount of blood leaving the heart per unit time
D. The amount of blood leaving the lung per unit time

Answer

**Step-by-Step Solution:**

1. **Understanding Cardiac Output**:
- Cardiac output is defined as the volume of blood that the heart pumps out in one minute. It is also referred to as minute volume.

2. **Significance of Cardiac Output**:
- Cardiac output signifies the amount of blood being ejected from the heart into the greater arteries each minute. This is crucial for understanding how well the heart is functioning and how efficiently it is supplying blood to the body.

3. **Normal Values**:
- For a normal, healthy young adult, the average cardiac output is approximately 5.6 liters per minute. This value can vary based on factors such as age, health, and physical condition.

4. **Formula for Cardiac Output**:
- The formula to calculate cardiac output is:
\[ \text{Cardiac Output} = \text{Stroke Volume} \times \text{Heart Rate} \]
- Here, stroke volume refers to the amount of blood pumped by the heart with each beat, and heart rate is the number of beats per minute.

5. **Conclusion**:
- Therefore, cardiac output signifies the amount of blood leaving the heart per unit time.

**Final Answer**: Cardiac output signifies the amount of blood leaving the heart per unit time.

---