An efficient way for the body to alter its cardiac output is to change the heart's stroke volume. Stroke volume depends both on how much blood is in the heart at the end of diastole and how much remains at the termination of ejection. The German physiologist Otto Frank was the first investigator to systematically examine how stroke volume is controlled. His research demonstrated that the amount of ventricular pressure actively generated by a frog's contracting heart depends on the volume of fluid within the ventricle at the end of diastole. A fluid-filled balloon was placed within the ventricle of a beating frog's heart and the pressure inside the balloon was measured with a catheter. The balloon was then filled to different volumes and ventricular pressure was recorded at each volume both during diastole and systole. The left panel of Fig. 4 shows the time course of the ventricular pressure for four different volumes. The right panel shows a plot of the pressures against the volume in the balloon. The solid curve is for the peak pressure achieved during systole and the dashed curve is for the pressure during diastole. The plot reveals that over a wide range the greater the distention of the heart during diastole, the more forcibly
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One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.