Cardiac function does not require intact innervations. Frog's heart removed from the body, and in human beings who have transplanted heart, the heart continues to function. The perfusion of the isolated heart in the laboratory will also continue to beat at regular intervals. In a frog's heart when the chambers are separated, each of the chambers shows regular contractions on [...]
The following points highlight the top eight factors affecting venous return. The factors are: 1. Pressure Gradient 2. Vis-a-Tergo 3. Vis-a-Fronte 4. Skeletal Muscle Pump 5. Thoracic Pump 6. Abdominal Pump 7. Venomotor Tone 8. Posture and Gravity. Factor # 1. Pressure Gradient: The pressure in the right atria (central venous pressure) into which the superior and inferior vena cavae [...]
In this article we will discuss about:- 1. Meaning of Cardiac Cycle 2. Duration of Cardiac Cycle 3. Phases. Meaning of Cardiac Cycle: SA node, the pacemaker has the property of automaticity and rhythmicity. Because of this, it produces action potentials, which spread all along the atrial and ventricular muscle fibers. This in turn brings about depolarization and repolarization. Following [...]