5 Written questions
5 Matching questions
- Posterior interventricular artery
- Absolute refractory period
- Refractory periods
- Depolarization Phase
- a Period following effective stimulation during which excitable tissue, such as heart muscle, fails to respond to a stimulus of threshold intensity.
- b (visceral Pericardium), is a thin serous membrane that constitutes the smooth, outer surface of the heart. Also called the serous pericardium.
- c A branch of the right coronary artery, lies in the posterior interventricular sulcus and supplies blood to the posterior and inferior part of the heart.
- d Change in the electric charge difference across the plasma membrane that causes the difference to be smaller or closer to 0 mV; phase of the action potential in which the membrane potential moves toward zero, or becomes positive.
- e The Cardiac muscle cell is completely insensitive to further stimulation. Portion of the action potential during which the membrane is insensitive to all stimuli, regardless of their strength.
5 Multiple choice questions
- The thick middle layer of the heart, is composed of cardiac muscle cells and is responsible for the heart's ability to contract.
- Specialized plasma membrane structures hold the cells together.
- membrane channels open, bringing about the depolarization phase of the action potential.
- Several types exist, each of which opens and closes at different membrane potentials, causing changes in membrane permeability to K+.
- is relaxation of the ventricular myocardium
5 True/False questions
Heart rate (HR) → Consists of a plate of fibrous connective tissue between the atria and the ventricles. This connective tissue plate forms fibrous rings around the atrioventricular and the semilunar valves and provides solid support for them, reinforcing the valve openings.
Preload → is the pressure the contracting left ventricle must produce to overcome the pressure in the aorta and move blood into the aorta.
Circumflex artery → branches from the left coronary artery and extends around to the posterior side of the heart in the coronary sulcus. Its branches supply blood to much of the posterior wall of the heart.
Pericardial fluid → helps reduce friction as the heart moves within the pericardial sac.
Electrocardiogram (ECG or EKG) → The summated record of cardiac action potentials. Graphic record of the heart's electric currents obtained with an electrocardiograph.