Which chamber of the heart shows the greatest pressure changes during one cardiac cycle?

Options

A. Left atrium
B. Left Ventricle
C. Right atrium
D. Right ventricle

Answer

To determine which chamber of the heart shows the greatest pressure changes during one cardiac cycle, we can follow these steps:

### Step 1: Understand the Cardiac Cycle
The cardiac cycle consists of two main phases: systole (contraction) and diastole (relaxation). During systole, the heart chambers contract and pump blood, while during diastole, they relax and fill with blood.

### Step 2: Identify the Chambers of the Heart
The heart has four chambers:
1. Right atrium
2. Right ventricle
3. Left atrium
4. Left ventricle

### Step 3: Focus on the Left Ventricle
Among these chambers, the left ventricle is responsible for pumping oxygenated blood to the entire body. It generates the highest pressure to overcome the systemic vascular resistance.

### Step 4: Analyze Pressure Changes
During ventricular systole (approximately 0.3 seconds), the left ventricle contracts and the pressure within it rises significantly to push blood into the aorta. This pressure can reach up to 120 mmHg or more. Conversely, during ventricular diastole (approximately 0.5 seconds), the pressure drops as the ventricle fills with blood from the left atrium.

### Step 5: Conclusion
Given that the left ventricle experiences such a dramatic increase in pressure during systole and a notable decrease during diastole, it shows the greatest pressure changes during one cardiac cycle compared to the other chambers.

### Final Answer
The chamber of the heart that shows the greatest pressure changes during one cardiac cycle is the **left ventricle**.

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