Cardio physiology Flashcards
What is the function of the atrioventricular valves ?
when the ventricles contract the AV valves close to prevent blood from flowing back into the atria
What is the function of the semilunar valves
when the ventricles relax the semilunar valves close to prevent blood following back into the ventricles
Describe the heart conduction system
it is a network of nodes, cells and signals that control your heartbeat. Each time the heart beats electrical signals travel through the heart causing different parts of the heart to expand and contract.
What is a ECG
a device that measures the electrical activity of the heart and records the movement of the movement of the heart.
What is a normal ECG?
60-100 beats a minute
What does a abnormal ECG indicate
signal of a medical emergency such as heart attack
What is cardiac output
the amount of blood the heart pumps out through the circulatory system per minute. It is the product of the heart rate x stroke volume
What is stroke volume
The volume of blood being ejected during ventricular contraction
What can affect your heartbeat
emotions, temperature, chemicals, gender and age
What regulates your heartbeat
the autonomic nervous system
What is systemic blood pressure
the force per unit area in which blood is pushed against the walls of the blood vessels . The average bp is 120/70
what factors can affect blood pressure?
hydrostatic pressure and gravity blood volume vessel elasticity cardiac output blood viscosity
What is venous return
the rate of blood flow back to heart
State and describe three mechanisms to promote venous return
smooth muscle and valves hep squeeze blood towards the heart
skeletal muscle pump compress underlying veins in order to increase blood flow to the heart
respiratory pump causes muscles to contract an relax during breathing and these pressure chances in the thoracic and abdominal cavities compress the nearby veins and assist venous return
Why is maintaining blood pressure important?
It is vital for proper organ function
