During cardiac cycle about _______________% of ventricular filling occurs prior to atrial contraction. ______________% ventricu-lar filling occurs due to atrial contraction-

Options

A. 50, 50
B. 70, 30
C. 30, 70
D. 10, 90

Answer

To solve the question regarding the percentages of ventricular filling during the cardiac cycle, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Cardiac Cycle**: The cardiac cycle consists of various phases, including ventricular filling, contraction, and relaxation. During this cycle, blood fills the ventricles from the atria.

2. **Ventricular Filling Before Atrial Contraction**: It is important to note that the ventricles fill with blood even before the atria contract. This is due to the passive flow of blood from the atria into the ventricles.

3. **Percentage of Ventricular Filling**: According to the information provided, approximately 70% of the ventricular filling occurs passively before the atrial contraction. This means that the majority of the blood volume in the ventricles is already present before the atria contract.

4. **Ventricular Filling Due to Atrial Contraction**: The remaining 30% of the ventricular filling occurs as a result of the atrial contraction. When the atria contract, they push additional blood into the ventricles, completing the filling process.

5. **Final Answer**: Therefore, the final answer to the question is:
- During the cardiac cycle, about **70%** of ventricular filling occurs prior to atrial contraction, and **30%** of ventricular filling occurs due to atrial contraction.