The Cardiac Cycle Flashcards
What is atrial systole?
The artia contacts so the volume of the atria reduces and so increases the pressure of blood, when pressure exceeds that’s of the ventricles the atrioventricular valves open forcing blood into the ventricles.
what is ventricular systole?
ventricles contract decreasing the volume in the ventricles and so increases the pressure forcing the atrioventricular valves to close as pressure in the ventricles exceeds that of the atria and semi lunar valves are forced open and blood is pumped out through the arteries
What is diastole?
both atria and ventricles relax so their volume increases and pressure decreases, the pressure in the arteries is greater than the ventricles so the semi lumar valves shut and blood enters the atria from the veins increasing pressure of the atria, eventually exceeding ventricle pressure and AV valves open and blood begins to passively flow into the ventricles
what is the calculation for calculating cardiac output?
cardiac output = stroke volume × heart rate
Explain how the highest blood pressure is produced in the left venricle?
The thick muscle creates an increased contraction therefore that increases the blood pressure
Some babys are born with a hle between the right and left ventricles, these babys are unable to get enough oxygen to there tissues, suggest why?
The hole will decrease the blood presure so the semi-lunar valves will not open so there is a lower volume of oxygenated blood, which is also mixed with deoxygenated blood, leaving to ventricles to the aorta to be pumped around the body, so less oxyenated blood is reaching their tissues.
Explain how the heart muscle and the heart valves maintain a one-way flow of blood from the left atrium to the aorta.
Blood enters the left atrium and the pressure in the atria is higher than that of the ventricles so the atrioventricular valves open and blood is forced into the ventricles. The semi-lunar valves remain shut as the pulmonary arteries exeed the pressure in the ventricles
