PSIO 202 Final Study Guide
Final Study Guide-PSIO 36 questions
Unit 1
1. Vena cava--right atrium--tricuspid valve--right ventricle--pulmonary valve--pulmonary artery--pulmonary vein--left atrium--bicuspid valve--left ventricle--aortic valve--aorta
2. SA node--AV node--AV bundle--right and left bundle branches--conducting myofibers (purkinje fibers) a. pacemaker cells in SA node spontaneously discharge action potentials at a rate of 100-120+ per minute *AP process: 1. depolarization due to na inflow when voltage gated Na channels open
2. plateau- due to Ca inflow when voltage gated slow ca channels open and K outflow when some k channel open
3. repolarization- due to closure of Ca channels and K outflow when additional voltage gated K channels open
*autonomic nerves modify the rate of discharge so that the resting heart rate is about 70 b/min b. the atria and ventricles must contract in a coordinated fashion
Sequence:
a. SA node contracts generating nerve impulses that travels throughout the heart wall. This causes both atria to contract
2. AV node impulse conduction(refractory period)
a. Impulses from the SA node reach the AV and are delayed in order to allow the atria to contract and empty)
3. AV bundle impulse conduction
a. Impulses are sent down to the atrioventricular bundle. This bundle of fibers branches off into two bundles and the impulses are carried down the center of the heart to the left and right ventricles
4. Purkinje fibers impulse conduction
a. At the base of the heat the atrioventricular bundles start to divide further into purkinje fibers. When the impulse reaches these fibers, they trigger the muscles fibers in the ventricles to contract. The right ventricle sends blood to the lungs via the pulmonary artery. Then the left ventricle pumps blood to the aorta
3. Stroke volume- amount of blood ejected by the ventricles in one contraction ventricular systole- starts when the AV valves close and the pressure within the ventricles begin to rise as the cardiac muscle
Unit 1
1. Vena cava--right atrium--tricuspid valve--right ventricle--pulmonary valve--pulmonary artery--pulmonary vein--left atrium--bicuspid valve--left ventricle--aortic valve--aorta
2. SA node--AV node--AV bundle--right and left bundle branches--conducting myofibers (purkinje fibers) a. pacemaker cells in SA node spontaneously discharge action potentials at a rate of 100-120+ per minute *AP process: 1. depolarization due to na inflow when voltage gated Na channels open
2. plateau- due to Ca inflow when voltage gated slow ca channels open and K outflow when some k channel open
3. repolarization- due to closure of Ca channels and K outflow when additional voltage gated K channels open
*autonomic nerves modify the rate of discharge so that the resting heart rate is about 70 b/min b. the atria and ventricles must contract in a coordinated fashion
Sequence:
a. SA node contracts generating nerve impulses that travels throughout the heart wall. This causes both atria to contract
2. AV node impulse conduction(refractory period)
a. Impulses from the SA node reach the AV and are delayed in order to allow the atria to contract and empty)
3. AV bundle impulse conduction
a. Impulses are sent down to the atrioventricular bundle. This bundle of fibers branches off into two bundles and the impulses are carried down the center of the heart to the left and right ventricles
4. Purkinje fibers impulse conduction
a. At the base of the heat the atrioventricular bundles start to divide further into purkinje fibers. When the impulse reaches these fibers, they trigger the muscles fibers in the ventricles to contract. The right ventricle sends blood to the lungs via the pulmonary artery. Then the left ventricle pumps blood to the aorta
3. Stroke volume- amount of blood ejected by the ventricles in one contraction ventricular systole- starts when the AV valves close and the pressure within the ventricles begin to rise as the cardiac muscle